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Ji QX, Liu P, Jin W, Guo J, Wu L, Yuan Z, Peters J, Feshali A, Paniccia M, Bowers JE, Vahala KJ. Multimodality integrated microresonators using the Moiré speedup effect. Science 2024; 383:1080-1083. [PMID: 38452084 DOI: 10.1126/science.adk9429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 01/10/2024] [Indexed: 03/09/2024]
Abstract
High-Q microresonators are indispensable components of photonic integrated circuits and offer several useful operational modes. However, these modes cannot be reconfigured after fabrication because they are fixed by the resonator's physical geometry. In this work, we propose a Moiré speedup dispersion tuning method that enables a microresonator device to operate in any of three modes. Electrical tuning of Vernier coupled rings switches operating modality to Brillouin laser, bright microcomb, and dark microcomb operation on demand using the same hybrid-integrated device. Brillouin phase matching and microcomb operation across the telecom C-band is demonstrated. Likewise, by using a single-pump wavelength, the operating mode can be switched. As a result, one universal design can be applied across a range of applications. The device brings flexible mixed-mode operation to integrated photonic circuits.
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Affiliation(s)
- Qing-Xin Ji
- T. J. Watson Laboratory of Applied Physics, Caltech, Pasadena, CA 91125, USA
| | - Peng Liu
- T. J. Watson Laboratory of Applied Physics, Caltech, Pasadena, CA 91125, USA
| | - Warren Jin
- ECE Department, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
- Anello Photonics, Santa Clara, CA 95054, USA
| | - Joel Guo
- ECE Department, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Lue Wu
- T. J. Watson Laboratory of Applied Physics, Caltech, Pasadena, CA 91125, USA
| | - Zhiquan Yuan
- T. J. Watson Laboratory of Applied Physics, Caltech, Pasadena, CA 91125, USA
| | - Jonathan Peters
- ECE Department, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Avi Feshali
- Anello Photonics, Santa Clara, CA 95054, USA
| | | | - John E Bowers
- ECE Department, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Kerry J Vahala
- T. J. Watson Laboratory of Applied Physics, Caltech, Pasadena, CA 91125, USA
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2
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Kudelin I, Groman W, Ji QX, Guo J, Kelleher ML, Lee D, Nakamura T, McLemore CA, Shirmohammadi P, Hanifi S, Cheng H, Jin N, Wu L, Halladay S, Luo Y, Dai Z, Jin W, Bai J, Liu Y, Zhang W, Xiang C, Chang L, Iltchenko V, Miller O, Matsko A, Bowers SM, Rakich PT, Campbell JC, Bowers JE, Vahala KJ, Quinlan F, Diddams SA. Photonic chip-based low-noise microwave oscillator. Nature 2024; 627:534-539. [PMID: 38448599 PMCID: PMC10954552 DOI: 10.1038/s41586-024-07058-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 01/11/2024] [Indexed: 03/08/2024]
Abstract
Numerous modern technologies are reliant on the low-phase noise and exquisite timing stability of microwave signals. Substantial progress has been made in the field of microwave photonics, whereby low-noise microwave signals are generated by the down-conversion of ultrastable optical references using a frequency comb1-3. Such systems, however, are constructed with bulk or fibre optics and are difficult to further reduce in size and power consumption. In this work we address this challenge by leveraging advances in integrated photonics to demonstrate low-noise microwave generation via two-point optical frequency division4,5. Narrow-linewidth self-injection-locked integrated lasers6,7 are stabilized to a miniature Fabry-Pérot cavity8, and the frequency gap between the lasers is divided with an efficient dark soliton frequency comb9. The stabilized output of the microcomb is photodetected to produce a microwave signal at 20 GHz with phase noise of -96 dBc Hz-1 at 100 Hz offset frequency that decreases to -135 dBc Hz-1 at 10 kHz offset-values that are unprecedented for an integrated photonic system. All photonic components can be heterogeneously integrated on a single chip, providing a significant advance for the application of photonics to high-precision navigation, communication and timing systems.
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Affiliation(s)
- Igor Kudelin
- National Institute of Standards and Technology, Boulder, CO, USA.
- Department of Physics, University of Colorado Boulder, Boulder, CO, USA.
| | - William Groman
- National Institute of Standards and Technology, Boulder, CO, USA
- Department of Physics, University of Colorado Boulder, Boulder, CO, USA
| | - Qing-Xin Ji
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, USA
| | - Joel Guo
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Megan L Kelleher
- National Institute of Standards and Technology, Boulder, CO, USA
- Department of Physics, University of Colorado Boulder, Boulder, CO, USA
| | - Dahyeon Lee
- National Institute of Standards and Technology, Boulder, CO, USA
- Department of Physics, University of Colorado Boulder, Boulder, CO, USA
| | - Takuma Nakamura
- National Institute of Standards and Technology, Boulder, CO, USA
- Department of Physics, University of Colorado Boulder, Boulder, CO, USA
| | - Charles A McLemore
- National Institute of Standards and Technology, Boulder, CO, USA
- Department of Physics, University of Colorado Boulder, Boulder, CO, USA
| | - Pedram Shirmohammadi
- Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA, USA
| | - Samin Hanifi
- Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA, USA
| | - Haotian Cheng
- Department of Applied Physics, Yale University, New Haven, CT, USA
| | - Naijun Jin
- Department of Applied Physics, Yale University, New Haven, CT, USA
| | - Lue Wu
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, USA
| | - Samuel Halladay
- Department of Applied Physics, Yale University, New Haven, CT, USA
| | - Yizhi Luo
- Department of Applied Physics, Yale University, New Haven, CT, USA
| | - Zhaowei Dai
- Department of Applied Physics, Yale University, New Haven, CT, USA
| | - Warren Jin
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Junwu Bai
- Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA, USA
| | - Yifan Liu
- National Institute of Standards and Technology, Boulder, CO, USA
- Department of Physics, University of Colorado Boulder, Boulder, CO, USA
| | - Wei Zhang
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Chao Xiang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Lin Chang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Vladimir Iltchenko
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Owen Miller
- Department of Applied Physics, Yale University, New Haven, CT, USA
| | - Andrey Matsko
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Steven M Bowers
- Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA, USA
| | - Peter T Rakich
- Department of Applied Physics, Yale University, New Haven, CT, USA
| | - Joe C Campbell
- Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA, USA
| | - John E Bowers
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Kerry J Vahala
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, USA
| | - Franklyn Quinlan
- National Institute of Standards and Technology, Boulder, CO, USA
- Electrical Computer & Energy Engineering, University of Colorado Boulder, Boulder, CO, USA
| | - Scott A Diddams
- National Institute of Standards and Technology, Boulder, CO, USA.
- Department of Physics, University of Colorado Boulder, Boulder, CO, USA.
- Electrical Computer & Energy Engineering, University of Colorado Boulder, Boulder, CO, USA.
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3
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Morin TJ, Peters J, Li M, Guo J, Wan Y, Xiang C, Bowers JE. Coprocessed heterogeneous near-infrared lasers on thin-film lithium niobate. Opt Lett 2024; 49:1197-1200. [PMID: 38426972 DOI: 10.1364/ol.516486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 02/06/2024] [Indexed: 03/02/2024]
Abstract
Thin-film lithium niobate (TFLN) is an attractive platform for photonic applications on account of its wide bandgap, its large electro-optic coefficient, and its large nonlinearity. Since these characteristics are used in systems that require a coherent light source, size, weight, power, and cost can be reduced and reliability enhanced by combining TFLN processing and heterogeneous laser fabrication. Here, we report the fabrication of laser devices on a TFLN wafer and also the coprocessing of five different GaAs-based III-V epitaxial structures, including InGaAs quantum wells and InAs quantum dots. Lasing is observed at wavelengths near 930, 1030, and 1180 nm, which, if frequency-doubled using TFLN, would produce blue, green, and orange visible light. A single-sided power over 25 mW is measured with an integrating sphere.
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4
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Hughes ET, Shang C, Selvidge J, Jung D, Wan Y, Herrick RW, Bowers JE, Mukherjee K. Gradual degradation in InAs quantum dot lasers on Si and GaAs. Nanoscale 2024; 16:2966-2973. [PMID: 38251961 DOI: 10.1039/d3nr05311c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2024]
Abstract
Reliable quantum dot lasers on silicon are a key remaining challenge to successful integrated silicon photonics. In this work, quantum dot (QD) lasers on silicon with and without misfit dislocation trapping layers are aged for 12 000 hours and are compared to QD lasers on native GaAs aged for 8400 hours. The non-trapping-layer (TL) laser on silicon degrades heavily during this time, but much more modest gradual degradation is observed for the other two devices. Electroluminescence imaging reveals relatively uniform gradual dimming for the aged TL laser on silicon. At the same time, we find nanoscale dislocation loop defects throughout the quantum dot-based active region of all three aged lasers via electron microscopy. The Burgers vector of these loops is consistent with . We suggest that the primary source of degradation, however, is the generation and migration of point defects that substantially enhance non-radiative recombination in the active region, the visible symptom of which is the formation of dislocation loops. To prevent this, we propose that laser fabrication should be switched from deeply etched to shallow etch ridges where the active region remains intact near the mesa. Additionally, post-growth annealing and altered growth conditions in the active region should be explored to minimize the grown-in point defect density.
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Affiliation(s)
- Eamonn T Hughes
- Materials Department, University of California Santa Barbara, Santa Barbara, California, USA.
| | - Chen Shang
- Materials Department, University of California Santa Barbara, Santa Barbara, California, USA.
| | - Jennifer Selvidge
- Materials Department, University of California Santa Barbara, Santa Barbara, California, USA.
- National Renewable Energy Laboratory, Golden, CO, USA
| | - Daehwan Jung
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, California, USA
- Center for Opto-electronic Materials and Devices, Korea Institute of Science and Technology, Seoul, South Korea
| | - Yating Wan
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, California, USA
- Integrated Photonics Lab, Computer, Electrical and Mathematical Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | | | - John E Bowers
- Materials Department, University of California Santa Barbara, Santa Barbara, California, USA.
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, California, USA
| | - Kunal Mukherjee
- Department of Materials Science and Engineering, Stanford University, Stanford, California, USA.
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5
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Shekhar S, Bogaerts W, Chrostowski L, Bowers JE, Hochberg M, Soref R, Shastri BJ. Roadmapping the next generation of silicon photonics. Nat Commun 2024; 15:751. [PMID: 38272873 PMCID: PMC10811194 DOI: 10.1038/s41467-024-44750-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 01/03/2024] [Indexed: 01/27/2024] Open
Abstract
Silicon photonics has developed into a mainstream technology driven by advances in optical communications. The current generation has led to a proliferation of integrated photonic devices from thousands to millions-mainly in the form of communication transceivers for data centers. Products in many exciting applications, such as sensing and computing, are around the corner. What will it take to increase the proliferation of silicon photonics from millions to billions of units shipped? What will the next generation of silicon photonics look like? What are the common threads in the integration and fabrication bottlenecks that silicon photonic applications face, and which emerging technologies can solve them? This perspective article is an attempt to answer such questions. We chart the generational trends in silicon photonics technology, drawing parallels from the generational definitions of CMOS technology. We identify the crucial challenges that must be solved to make giant strides in CMOS-foundry-compatible devices, circuits, integration, and packaging. We identify challenges critical to the next generation of systems and applications-in communication, signal processing, and sensing. By identifying and summarizing such challenges and opportunities, we aim to stimulate further research on devices, circuits, and systems for the silicon photonics ecosystem.
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Affiliation(s)
- Sudip Shekhar
- Department of Electrical & Computer Engineering, University of British Columbia, 2332 Main Mall, Vancouver, V6T1Z4, BC, Canada.
| | - Wim Bogaerts
- Department of Information Technology, Ghent University - IMEC, Technologiepark-Zwijnaarde 126, Ghent, 9052, Belgium
| | - Lukas Chrostowski
- Department of Electrical & Computer Engineering, University of British Columbia, 2332 Main Mall, Vancouver, V6T1Z4, BC, Canada
| | - John E Bowers
- Department of Electrical & Computer Engineering, University of California Santa Barbara, Santa Barbara, 93106, CA, USA
| | - Michael Hochberg
- Luminous Computing, 4750 Patrick Henry Drive, Santa Clara, 95054, CA, USA
| | - Richard Soref
- College of Science and Mathematics, University of Massachusetts Boston, 100 William T. Morrissey Blvd., Boston, 02125, MA, USA
| | - Bhavin J Shastri
- Department of Physics, Engineering Physics & Astronomy, Queen's University, 64 Bader Lane, Kingston, K7L3N6, ON, Canada.
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6
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Razumov A, Heebøll HR, Dummont M, Terra O, Dong B, Riebesehl J, Varming P, Pedersen JE, Ros FD, Bowers JE, Zibar D. Subspace tracking for phase noise source separation in frequency combs. Opt Express 2023; 31:34325-34347. [PMID: 37859192 DOI: 10.1364/oe.495663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 09/20/2023] [Indexed: 10/21/2023]
Abstract
It is widely acknowledged that the phase noise of an optical frequency comb primarily stems from the common mode (carrier-envelope) and the repetition rate phase noise. However, owing to technical noise sources or other intricate intra-cavity factors, residual phase noise components, distinct from the common mode and the repetition rate phase noise, may also exist. We introduce a measurement technique that combines subspace tracking and multi-heterodyne coherent detection for the separation of different phase noise sources. This method allows us to break down the overall phase noise sources associated with a specific comb-line into distinct phase noise components associated with the common mode, the repetition rate and the residual phase noise terms. The measurement method allow us, for the first time, to identify and measure residual phase noise sources of a frequency modulated mode-locked laser.
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7
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Wu L, Xie W, Chen HJ, Colburn K, Xiang C, Chang L, Jin W, Liu JY, Yu Y, Yamamoto Y, Bowers JE, Suh MG, Vahala KJ. AlGaAs soliton microcombs at room temperature. Opt Lett 2023; 48:3853-3856. [PMID: 37527066 DOI: 10.1364/ol.484552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 05/21/2023] [Indexed: 08/03/2023]
Abstract
Soliton mode locking in high-Q microcavities provides a way to integrate frequency comb systems. Among material platforms, AlGaAs has one of the largest optical nonlinearity coefficients, and is advantageous for low-pump-threshold comb generation. However, AlGaAs also has a very large thermo-optic effect that destabilizes soliton formation, and femtosecond soliton pulse generation has only been possible at cryogenic temperatures. Here, soliton generation in AlGaAs microresonators at room temperature is reported for the first time, to the best of our knowledge. The destabilizing thermo-optic effect is shown to instead provide stability in the high-repetition-rate soliton regime (corresponding to a large, normalized second-order dispersion parameter D2/κ). Single soliton and soliton crystal generation with sub-milliwatt optical pump power are demonstrated. The generality of this approach is verified in a high-Q silica microtoroid where manual tuning into the soliton regime is demonstrated. Besides the advantages of large optical nonlinearity, these AlGaAs devices are natural candidates for integration with semiconductor pump lasers. Furthermore, the approach should generalize to any high-Q resonator material platform.
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8
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Xiang C, Jin W, Terra O, Dong B, Wang H, Wu L, Guo J, Morin TJ, Hughes E, Peters J, Ji QX, Feshali A, Paniccia M, Vahala KJ, Bowers JE. 3D integration enables ultralow-noise isolator-free lasers in silicon photonics. Nature 2023; 620:78-85. [PMID: 37532812 PMCID: PMC10396957 DOI: 10.1038/s41586-023-06251-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Accepted: 05/23/2023] [Indexed: 08/04/2023]
Abstract
Photonic integrated circuits are widely used in applications such as telecommunications and data-centre interconnects1-5. However, in optical systems such as microwave synthesizers6, optical gyroscopes7 and atomic clocks8, photonic integrated circuits are still considered inferior solutions despite their advantages in size, weight, power consumption and cost. Such high-precision and highly coherent applications favour ultralow-noise laser sources to be integrated with other photonic components in a compact and robustly aligned format-that is, on a single chip-for photonic integrated circuits to replace bulk optics and fibres. There are two major issues preventing the realization of such envisioned photonic integrated circuits: the high phase noise of semiconductor lasers and the difficulty of integrating optical isolators directly on-chip. Here we challenge this convention by leveraging three-dimensional integration that results in ultralow-noise lasers with isolator-free operation for silicon photonics. Through multiple monolithic and heterogeneous processing sequences, direct on-chip integration of III-V gain medium and ultralow-loss silicon nitride waveguides with optical loss around 0.5 decibels per metre are demonstrated. Consequently, the demonstrated photonic integrated circuit enters a regime that gives rise to ultralow-noise lasers and microwave synthesizers without the need for optical isolators, owing to the ultrahigh-quality-factor cavity. Such photonic integrated circuits also offer superior scalability for complex functionalities and volume production, as well as improved stability and reliability over time. The three-dimensional integration on ultralow-loss photonic integrated circuits thus marks a critical step towards complex systems and networks on silicon.
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Affiliation(s)
- Chao Xiang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA.
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, China.
| | - Warren Jin
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA
- Anello Photonics, Santa Clara, CA, USA
| | - Osama Terra
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA
- Primary Length and Laser Technology Lab, National Institute of Standards, Giza, Egypt
| | - Bozhang Dong
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Heming Wang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Lue Wu
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, USA
| | - Joel Guo
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Theodore J Morin
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Eamonn Hughes
- Materials Department, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Jonathan Peters
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Qing-Xin Ji
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, USA
| | | | | | - Kerry J Vahala
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, USA
| | - John E Bowers
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA.
- Materials Department, University of California, Santa Barbara, Santa Barbara, CA, USA.
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9
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Dong B, Dumont M, Terra O, Wang H, Netherton A, Bowers JE. Broadband quantum-dot frequency-modulated comb laser. Light Sci Appl 2023; 12:182. [PMID: 37491305 PMCID: PMC10368713 DOI: 10.1038/s41377-023-01225-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 07/06/2023] [Accepted: 07/09/2023] [Indexed: 07/27/2023]
Abstract
Frequency-modulated (FM) laser combs, which offer a quasi-continuous-wave output and a flat-topped optical spectrum, are emerging as a promising solution for wavelength-division multiplexing applications, precision metrology, and ultrafast optical ranging. The generation of FM combs relies on spatial hole burning, group velocity dispersion, Kerr nonlinearity, and four-wave mixing (FWM). While FM combs have been widely observed in quantum cascade Fabry-Perot (FP) lasers, the requirement for a low-dispersion FP cavity can be a challenge in platforms where the waveguide dispersion is mainly determined by the material. Here we report a 60 GHz quantum-dot (QD) mode-locked laser in which both the amplitude-modulated (AM) and the FM comb can be generated independently. The high FWM efficiency of -5 dB allows the QD laser to generate FM comb efficiently. We also demonstrate that the Kerr nonlinearity can be practically engineered to improve the FM comb bandwidth without the need for GVD engineering. The maximum 3-dB bandwidth that our QD platform can deliver is as large as 2.2 THz. This study gives novel insights into the improvement of FM combs and paves the way for small-footprint, electrically pumped, and energy-efficient frequency combs for silicon photonic integrated circuits (PICs).
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Affiliation(s)
- Bozhang Dong
- Institute for Energy Efficiency, University of California, Santa Barbara, CA, USA.
| | - Mario Dumont
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, USA
| | - Osama Terra
- Institute for Energy Efficiency, University of California, Santa Barbara, CA, USA
- Primary Length and Laser Technology Lab, National Institute of Standards, Giza, Egypt
| | - Heming Wang
- Institute for Energy Efficiency, University of California, Santa Barbara, CA, USA
| | - Andrew Netherton
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, USA
| | - John E Bowers
- Institute for Energy Efficiency, University of California, Santa Barbara, CA, USA.
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, USA.
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10
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Netherton AM, Gao Y, Pestana N, Bovington J, Bowers JE. Athermal, fabrication-tolerant Si-SiN FIR filters for a silicon photonics foundry platform. Opt Express 2023; 31:23952-23965. [PMID: 37475235 DOI: 10.1364/oe.492543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 06/13/2023] [Indexed: 07/22/2023]
Abstract
A means of athermalizing unbalanced Mach-Zehnder interferometers on a 300 mm silicon photonics foundry platform utilizing Si and SiN layers to produce the path imbalance is demonstrated. This technique can be applied to all other forms of finite impulse response filters, such as arrayed waveguide gratings. Wafer scale performance of fabricated devices is analyzed for their expected performance in the target application: odd-even channel (de)-interleavers for dense wavelength division multiplexing links. Finally, a method is proposed to improve device performance to be more robust to fabrication variations while simultaneously maintaining athermality.
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11
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Alkhazraji E, Chow WW, Grillot F, Bowers JE, Wan Y. Linewidth narrowing in self-injection-locked on-chip lasers. Light Sci Appl 2023; 12:162. [PMID: 37380663 DOI: 10.1038/s41377-023-01172-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 04/25/2023] [Accepted: 04/26/2023] [Indexed: 06/30/2023]
Abstract
Stable laser emission with narrow linewidth is of critical importance in many applications, including coherent communications, LIDAR, and remote sensing. In this work, the physics underlying spectral narrowing of self-injection-locked on-chip lasers to Hz-level lasing linewidth is investigated using a composite-cavity structure. Heterogeneously integrated III-V/SiN lasers operating with quantum-dot and quantum-well active regions are analyzed with a focus on the effects of carrier quantum confinement. The intrinsic differences are associated with gain saturation and carrier-induced refractive index, which are directly connected with 0- and 2-dimensional carrier densities of states. Results from parametric studies are presented for tradeoffs involved with tailoring the linewidth, output power, and injection current for different device configurations. Though both quantum-well and quantum-dot devices show similar linewidth-narrowing capabilities, the former emits at a higher optical power in the self-injection-locked state, while the latter is more energy-efficient. Lastly, a multi-objective optimization analysis is provided to optimize the operation and design parameters. For the quantum-well laser, minimizing the number of quantum-well layers is found to decrease the threshold current without significantly reducing the output power. For the quantum-dot laser, increasing the quantum-dot layers or density in each layer increases the output power without significantly increasing the threshold current. These findings serve to guide more detailed parametric studies to produce timely results for engineering design.
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Affiliation(s)
- Emad Alkhazraji
- Integrated Photonics Lab, King Abdullah University of Science and Technology, Thuwal, 23955, Saudi Arabia
| | - Weng W Chow
- Sandia National Laboratories, Albuquerque, NM, 87185-1086, USA.
| | - Frédéric Grillot
- LTCI, Télécom Paris, Institut Polytechnique de Paris, 91120, Palaiseau, France
| | - John E Bowers
- Department of Electronic and Computer Engineering, University of California - Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Yating Wan
- Integrated Photonics Lab, King Abdullah University of Science and Technology, Thuwal, 23955, Saudi Arabia.
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12
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Koscica R, Wan Y, He W, Kennedy MJ, Bowers JE. Heterogeneous integration of a III-V quantum dot laser on high thermal conductivity silicon carbide. Opt Lett 2023; 48:2539-2542. [PMID: 37186702 DOI: 10.1364/ol.486089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Heat accumulation prevents semiconductor lasers from operating at their full potential. This can be addressed through heterogeneous integration of a III-V laser stack onto non-native substrate materials with high thermal conductivity. Here, we demonstrate III-V quantum dot lasers heterogeneously integrated on silicon carbide (SiC) substrates with high temperature stability. A large T0 of 221 K with a relatively temperature-insensitive operation occurs near room temperature, while lasing is sustained up to 105°C. The SiC platform presents a unique and ideal candidate for realizing monolithic integration of optoelectronics, quantum, and nonlinear photonics.
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13
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Lao C, Jin X, Chang L, Wang H, Lv Z, Xie W, Shu H, Wang X, Bowers JE, Yang QF. Quantum decoherence of dark pulses in optical microresonators. Nat Commun 2023; 14:1802. [PMID: 37002215 PMCID: PMC10066214 DOI: 10.1038/s41467-023-37475-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 03/16/2023] [Indexed: 04/03/2023] Open
Abstract
Quantum fluctuations disrupt the cyclic motions of dissipative Kerr solitons (DKSs) in nonlinear optical microresonators and consequently cause timing jitter of the emitted pulse trains. This problem is translated to the performance of several applications that employ DKSs as compact frequency comb sources. Recently, device manufacturing and noise reduction technologies have advanced to unveil the quantum properties of DKSs. Here we investigate the quantum decoherence of DKSs existing in normal-dispersion microresonators known as dark pulses. By virtue of the very large material nonlinearity, we directly observe the quantum decoherence of dark pulses in an AlGaAs-on-insulator microresonator, and the underlying dynamical processes are resolved by injecting stochastic photons into the microresonators. Moreover, phase correlation measurements show that the uniformity of comb spacing of quantum-limited dark pulses is better than 1.2 × 10-16 and 2.5 × 10-13 when normalized to the optical carrier frequencies and repetition frequencies, respectively. Comparing DKSs generated in different material platforms explicitly confirms the advantages of dark pulses over bright solitons in terms of quantum-limited coherence. Our work establishes a critical performance assessment of DKSs, providing guidelines for coherence engineering of chip-scale optical frequency combs.
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Affiliation(s)
- Chenghao Lao
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, 100871, Beijing, China
| | - Xing Jin
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, 100871, Beijing, China
| | - Lin Chang
- State Key Laboratory of Advanced Optical Communications System and Networks, School of Electronics, Peking University, 100871, Beijing, China
| | - Heming Wang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA
| | - Zhe Lv
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, 100871, Beijing, China
| | - Weiqiang Xie
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA
- State Key Lab of Advanced Optical Communication Systems and Networks, Department of Electronic Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Haowen Shu
- State Key Laboratory of Advanced Optical Communications System and Networks, School of Electronics, Peking University, 100871, Beijing, China
| | - Xingjun Wang
- State Key Laboratory of Advanced Optical Communications System and Networks, School of Electronics, Peking University, 100871, Beijing, China
| | - John E Bowers
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA.
| | - Qi-Fan Yang
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, 100871, Beijing, China.
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China.
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14
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Zhou Z, Ou X, Fang Y, Alkhazraji E, Xu R, Wan Y, Bowers JE. Prospects and applications of on-chip lasers. eLight 2023; 3:1. [PMID: 36618904 PMCID: PMC9810524 DOI: 10.1186/s43593-022-00027-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 09/03/2022] [Accepted: 09/05/2022] [Indexed: 01/05/2023]
Abstract
Integrated silicon photonics has sparked a significant ramp-up of investment in both academia and industry as a scalable, power-efficient, and eco-friendly solution. At the heart of this platform is the light source, which in itself, has been the focus of research and development extensively. This paper sheds light and conveys our perspective on the current state-of-the-art in different aspects of application-driven on-chip silicon lasers. We tackle this from two perspectives: device-level and system-wide points of view. In the former, the different routes taken in integrating on-chip lasers are explored from different material systems to the chosen integration methodologies. Then, the discussion focus is shifted towards system-wide applications that show great prospects in incorporating photonic integrated circuits (PIC) with on-chip lasers and active devices, namely, optical communications and interconnects, optical phased array-based LiDAR, sensors for chemical and biological analysis, integrated quantum technologies, and finally, optical computing. By leveraging the myriad inherent attractive features of integrated silicon photonics, this paper aims to inspire further development in incorporating PICs with on-chip lasers in, but not limited to, these applications for substantial performance gains, green solutions, and mass production.
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Affiliation(s)
- Zhican Zhou
- Integrated Photonics Lab, King Abdullah University of Science and Technology, Thuwal, Makkah Province Saudi Arabia
| | - Xiangpeng Ou
- Integrated Photonics Lab, King Abdullah University of Science and Technology, Thuwal, Makkah Province Saudi Arabia
| | - Yuetong Fang
- Function Hub, The Hong Kong University of Science and Technology (Guangzhou), Guangdong, China
| | - Emad Alkhazraji
- Integrated Photonics Lab, King Abdullah University of Science and Technology, Thuwal, Makkah Province Saudi Arabia
| | - Renjing Xu
- Function Hub, The Hong Kong University of Science and Technology (Guangzhou), Guangdong, China
| | - Yating Wan
- Integrated Photonics Lab, King Abdullah University of Science and Technology, Thuwal, Makkah Province Saudi Arabia
- Institute for Energy Efficiency, University of California, Santa Barbara, Santa Barbara, CA 93106 USA
| | - John E. Bowers
- Institute for Energy Efficiency, University of California, Santa Barbara, Santa Barbara, CA 93106 USA
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15
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Yang KY, Shirpurkar C, White AD, Zang J, Chang L, Ashtiani F, Guidry MA, Lukin DM, Pericherla SV, Yang J, Kwon H, Lu J, Ahn GH, Van Gasse K, Jin Y, Yu SP, Briles TC, Stone JR, Carlson DR, Song H, Zou K, Zhou H, Pang K, Hao H, Trask L, Li M, Netherton A, Rechtman L, Stone JS, Skarda JL, Su L, Vercruysse D, MacLean JPW, Aghaeimeibodi S, Li MJ, Miller DAB, Marom DM, Willner AE, Bowers JE, Papp SB, Delfyett PJ, Aflatouni F, Vučković J. Multi-dimensional data transmission using inverse-designed silicon photonics and microcombs. Nat Commun 2022; 13:7862. [PMID: 36543782 PMCID: PMC9772188 DOI: 10.1038/s41467-022-35446-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 12/02/2022] [Indexed: 12/24/2022] Open
Abstract
The use of optical interconnects has burgeoned as a promising technology that can address the limits of data transfer for future high-performance silicon chips. Recent pushes to enhance optical communication have focused on developing wavelength-division multiplexing technology, and new dimensions of data transfer will be paramount to fulfill the ever-growing need for speed. Here we demonstrate an integrated multi-dimensional communication scheme that combines wavelength- and mode- multiplexing on a silicon photonic circuit. Using foundry-compatible photonic inverse design and spectrally flattened microcombs, we demonstrate a 1.12-Tb/s natively error-free data transmission throughout a silicon nanophotonic waveguide. Furthermore, we implement inverse-designed surface-normal couplers to enable multimode optical transmission between separate silicon chips throughout a multimode-matched fibre. All the inverse-designed devices comply with the process design rules for standard silicon photonic foundries. Our approach is inherently scalable to a multiplicative enhancement over the state of the art silicon photonic transmitters.
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Affiliation(s)
- Ki Youl Yang
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA ,grid.38142.3c000000041936754XJohn A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA USA
| | - Chinmay Shirpurkar
- grid.170430.10000 0001 2159 2859The College of Optics and Photonics, University of Central Florida, Orlando, FL USA
| | - Alexander D. White
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA
| | - Jizhao Zang
- grid.94225.38000000012158463XTime and Frequency Division, National Institute of Standards and Technology, Boulder, CO USA ,grid.266190.a0000000096214564Department of Physics, University of Colorado, Boulder, CO USA
| | - Lin Chang
- grid.133342.40000 0004 1936 9676Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA USA
| | - Farshid Ashtiani
- grid.25879.310000 0004 1936 8972Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA USA
| | - Melissa A. Guidry
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA
| | - Daniil M. Lukin
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA
| | - Srinivas V. Pericherla
- grid.170430.10000 0001 2159 2859The College of Optics and Photonics, University of Central Florida, Orlando, FL USA
| | - Joshua Yang
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA
| | - Hyounghan Kwon
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA
| | - Jesse Lu
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA ,SPINS Photonics Inc, Hollister, CA USA
| | - Geun Ho Ahn
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA
| | - Kasper Van Gasse
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA
| | - Yan Jin
- grid.94225.38000000012158463XTime and Frequency Division, National Institute of Standards and Technology, Boulder, CO USA ,grid.266190.a0000000096214564Department of Physics, University of Colorado, Boulder, CO USA
| | - Su-Peng Yu
- grid.94225.38000000012158463XTime and Frequency Division, National Institute of Standards and Technology, Boulder, CO USA ,grid.266190.a0000000096214564Department of Physics, University of Colorado, Boulder, CO USA
| | - Travis C. Briles
- grid.94225.38000000012158463XTime and Frequency Division, National Institute of Standards and Technology, Boulder, CO USA
| | - Jordan R. Stone
- grid.94225.38000000012158463XTime and Frequency Division, National Institute of Standards and Technology, Boulder, CO USA
| | - David R. Carlson
- grid.94225.38000000012158463XTime and Frequency Division, National Institute of Standards and Technology, Boulder, CO USA ,Octave Photonics, Louisville, CO USA
| | - Hao Song
- grid.42505.360000 0001 2156 6853Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, CA USA
| | - Kaiheng Zou
- grid.42505.360000 0001 2156 6853Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, CA USA
| | - Huibin Zhou
- grid.42505.360000 0001 2156 6853Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, CA USA
| | - Kai Pang
- grid.42505.360000 0001 2156 6853Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, CA USA
| | - Han Hao
- grid.25879.310000 0004 1936 8972Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA USA
| | - Lawrence Trask
- grid.170430.10000 0001 2159 2859The College of Optics and Photonics, University of Central Florida, Orlando, FL USA
| | - Mingxiao Li
- grid.133342.40000 0004 1936 9676Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA USA
| | - Andy Netherton
- grid.133342.40000 0004 1936 9676Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA USA
| | - Lior Rechtman
- grid.9619.70000 0004 1937 0538Applied Physics Department, The Hebrew University of Jerusalem, Jerusalem, Israel
| | | | - Jinhee L. Skarda
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA
| | - Logan Su
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA
| | - Dries Vercruysse
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA
| | | | - Shahriar Aghaeimeibodi
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA
| | - Ming-Jun Li
- grid.417796.aCorning Incorporated, Corning, NY USA
| | - David A. B. Miller
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA
| | - Dan M. Marom
- grid.9619.70000 0004 1937 0538Applied Physics Department, The Hebrew University of Jerusalem, Jerusalem, Israel
| | | | - John E. Bowers
- grid.133342.40000 0004 1936 9676Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA USA
| | - Scott B. Papp
- grid.94225.38000000012158463XTime and Frequency Division, National Institute of Standards and Technology, Boulder, CO USA ,grid.266190.a0000000096214564Department of Physics, University of Colorado, Boulder, CO USA
| | - Peter J. Delfyett
- grid.170430.10000 0001 2159 2859The College of Optics and Photonics, University of Central Florida, Orlando, FL USA
| | - Firooz Aflatouni
- grid.25879.310000 0004 1936 8972Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA USA
| | - Jelena Vučković
- grid.168010.e0000000419368956E.L.Ginzton Laboratory, Stanford University, Stanford, CA USA ,SPINS Photonics Inc, Hollister, CA USA
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16
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Guo J, McLemore CA, Xiang C, Lee D, Wu L, Jin W, Kelleher M, Jin N, Mason D, Chang L, Feshali A, Paniccia M, Rakich PT, Vahala KJ, Diddams SA, Quinlan F, Bowers JE. Chip-based laser with 1-hertz integrated linewidth. Sci Adv 2022; 8:eabp9006. [PMID: 36306350 PMCID: PMC9616488 DOI: 10.1126/sciadv.abp9006] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 09/08/2022] [Indexed: 06/16/2023]
Abstract
Lasers with hertz linewidths at time scales of seconds are critical for metrology, timekeeping, and manipulation of quantum systems. Such frequency stability relies on bulk-optic lasers and reference cavities, where increased size is leveraged to reduce noise but with the trade-off of cost, hand assembly, and limited applications. Alternatively, planar waveguide-based lasers enjoy complementary metal-oxide semiconductor scalability yet are fundamentally limited from achieving hertz linewidths by stochastic noise and thermal sensitivity. In this work, we demonstrate a laser system with a 1-s linewidth of 1.1 Hz and fractional frequency instability below 10-14 to 1 s. This low-noise performance leverages integrated lasers together with an 8-ml vacuum-gap cavity using microfabricated mirrors. All critical components are lithographically defined on planar substrates, holding potential for high-volume manufacturing. Consequently, this work provides an important advance toward compact lasers with hertz linewidths for portable optical clocks, radio frequency photonic oscillators, and related communication and navigation systems.
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Affiliation(s)
- Joel Guo
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Charles A. McLemore
- National Institute of Standards and Technology, 325 Broadway, Boulder, CO 80305, USA
- Department of Physics, University of Colorado Boulder, 440 UCB Boulder, CO 80309, USA
| | - Chao Xiang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Dahyeon Lee
- National Institute of Standards and Technology, 325 Broadway, Boulder, CO 80305, USA
- Department of Physics, University of Colorado Boulder, 440 UCB Boulder, CO 80309, USA
| | - Lue Wu
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA 91125, USA
| | - Warren Jin
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Megan Kelleher
- National Institute of Standards and Technology, 325 Broadway, Boulder, CO 80305, USA
- Department of Physics, University of Colorado Boulder, 440 UCB Boulder, CO 80309, USA
| | - Naijun Jin
- Department of Applied Physics, Yale University, New Haven, CT 06520, USA
| | - David Mason
- Department of Applied Physics, Yale University, New Haven, CT 06520, USA
| | - Lin Chang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | | | | | - Peter T. Rakich
- Department of Applied Physics, Yale University, New Haven, CT 06520, USA
| | - Kerry J. Vahala
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA 91125, USA
| | - Scott A. Diddams
- National Institute of Standards and Technology, 325 Broadway, Boulder, CO 80305, USA
- Department of Physics, University of Colorado Boulder, 440 UCB Boulder, CO 80309, USA
- Department of Electrical, Computer, and Energy Engineering, University of Colorado Boulder, 425 UCB, Boulder, CO 80309, USA
| | - Franklyn Quinlan
- National Institute of Standards and Technology, 325 Broadway, Boulder, CO 80305, USA
- Department of Physics, University of Colorado Boulder, 440 UCB Boulder, CO 80309, USA
| | - John E. Bowers
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
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17
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Shang C, Feng K, Hughes ET, Clark A, Debnath M, Koscica R, Leake G, Herman J, Harame D, Ludewig P, Wan Y, Bowers JE. Electrically pumped quantum-dot lasers grown on 300 mm patterned Si photonic wafers. Light Sci Appl 2022; 11:299. [PMID: 36229447 PMCID: PMC9562411 DOI: 10.1038/s41377-022-00982-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 09/13/2022] [Accepted: 09/14/2022] [Indexed: 06/16/2023]
Abstract
Monolithic integration of quantum dot (QD) gain materials onto Si photonic platforms via direct epitaxial growth is a promising solution for on-chip light sources. Recent developments have demonstrated superior device reliability in blanket hetero-epitaxy of III-V devices on Si at elevated temperatures. Yet, thick, defect management epi designs prevent vertical light coupling from the gain region to the Si-on-Insulator waveguides. Here, we demonstrate the first electrically pumped QD lasers grown by molecular beam epitaxy on a 300 mm patterned (001) Si wafer with a butt-coupled configuration. Unique growth and fabrication challenges imposed by the template architecture have been resolved, contributing to continuous wave lasing to 60 °C and a maximum double-side output power of 126.6 mW at 20 °C with a double-side wall-plug efficiency of 8.6%. The potential for robust on-chip laser operation and efficient low-loss light coupling to Si photonic circuits makes this heteroepitaxial integration platform on Si promising for scalable and low-cost mass production.
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Affiliation(s)
- Chen Shang
- Materials Department, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Kaiyin Feng
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Eamonn T Hughes
- Materials Department, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | | | | | - Rosalyn Koscica
- Materials Department, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Gerald Leake
- RF SUNY Polytechnic Institute, Albany, NY, 12203, USA
| | - Joshua Herman
- RF SUNY Polytechnic Institute, Albany, NY, 12203, USA
| | - David Harame
- RF SUNY Polytechnic Institute, Albany, NY, 12203, USA
| | | | - Yating Wan
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - John E Bowers
- Materials Department, University of California Santa Barbara, Santa Barbara, CA, 93106, USA.
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA.
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18
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Li M, Chang L, Wu L, Staffa J, Ling J, Javid UA, Xue S, He Y, Lopez-Rios R, Morin TJ, Wang H, Shen B, Zeng S, Zhu L, Vahala KJ, Bowers JE, Lin Q. Integrated Pockels laser. Nat Commun 2022; 13:5344. [PMID: 36097269 PMCID: PMC9467990 DOI: 10.1038/s41467-022-33101-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 09/01/2022] [Indexed: 11/10/2022] Open
Abstract
The development of integrated semiconductor lasers has miniaturized traditional bulky laser systems, enabling a wide range of photonic applications. A progression from pure III-V based lasers to III-V/external cavity structures has harnessed low-loss waveguides in different material systems, leading to significant improvements in laser coherence and stability. Despite these successes, however, key functions remain absent. In this work, we address a critical missing function by integrating the Pockels effect into a semiconductor laser. Using a hybrid integrated III-V/Lithium Niobate structure, we demonstrate several essential capabilities that have not existed in previous integrated lasers. These include a record-high frequency modulation speed of 2 exahertz/s (2.0 × 1018 Hz/s) and fast switching at 50 MHz, both of which are made possible by integration of the electro-optic effect. Moreover, the device co-lases at infrared and visible frequencies via the second-harmonic frequency conversion process, the first such integrated multi-color laser. Combined with its narrow linewidth and wide tunability, this new type of integrated laser holds promise for many applications including LiDAR, microwave photonics, atomic physics, and AR/VR. On-Chip integration of laser systems led to impressive development in many field of application like LIDAR or AR/VR to cite a few. Here the authors harness Pockels effect in an integrated semiconductor platform achieving fast on-chip configurability of a narrow linewidth laser.
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Affiliation(s)
- Mingxiao Li
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, NY, 14627, USA
| | - Lin Chang
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Lue Wu
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Jeremy Staffa
- Institute of Optics, University of Rochester, Rochester, NY, 14627, USA
| | - Jingwei Ling
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, NY, 14627, USA
| | - Usman A Javid
- Institute of Optics, University of Rochester, Rochester, NY, 14627, USA
| | - Shixin Xue
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, NY, 14627, USA
| | - Yang He
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, NY, 14627, USA
| | | | - Theodore J Morin
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Heming Wang
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Boqiang Shen
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Siwei Zeng
- Department of Electrical and Computer Engineering, Center for Optical Materials Science and Engineering Technologies, Clemson University, Clemson, SC, 29634, USA
| | - Lin Zhu
- Department of Electrical and Computer Engineering, Center for Optical Materials Science and Engineering Technologies, Clemson University, Clemson, SC, 29634, USA
| | - Kerry J Vahala
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, 91125, USA.
| | - John E Bowers
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, CA, 93106, USA.
| | - Qiang Lin
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, NY, 14627, USA. .,Institute of Optics, University of Rochester, Rochester, NY, 14627, USA.
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19
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Xiang C, Guo J, Jin W, Wu L, Peters J, Xie W, Chang L, Shen B, Wang H, Yang QF, Kinghorn D, Paniccia M, Vahala KJ, Morton PA, Bowers JE. High-performance lasers for fully integrated silicon nitride photonics. Nat Commun 2021; 12:6650. [PMID: 34789737 PMCID: PMC8599668 DOI: 10.1038/s41467-021-26804-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 10/19/2021] [Indexed: 11/23/2022] Open
Abstract
Silicon nitride (SiN) waveguides with ultra-low optical loss enable integrated photonic applications including low noise, narrow linewidth lasers, chip-scale nonlinear photonics, and microwave photonics. Lasers are key components to SiN photonic integrated circuits (PICs), but are difficult to fully integrate with low-index SiN waveguides due to their large mismatch with the high-index III-V gain materials. The recent demonstration of multilayer heterogeneous integration provides a practical solution and enabled the first-generation of lasers fully integrated with SiN waveguides. However, a laser with high device yield and high output power at telecommunication wavelengths, where photonics applications are clustered, is still missing, hindered by large mode transition loss, non-optimized cavity design, and a complicated fabrication process. Here, we report high-performance lasers on SiN with tens of milliwatts output power through the SiN waveguide and sub-kHz fundamental linewidth, addressing all the aforementioned issues. We also show Hertz-level fundamental linewidth lasers are achievable with the developed integration techniques. These lasers, together with high-Q SiN resonators, mark a milestone towards a fully integrated low-noise silicon nitride photonics platform. This laser should find potential applications in LIDAR, microwave photonics and coherent optical communications.
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Affiliation(s)
- Chao Xiang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA.
| | - Joel Guo
- grid.133342.40000 0004 1936 9676Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA USA
| | - Warren Jin
- grid.133342.40000 0004 1936 9676Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA USA
| | - Lue Wu
- grid.20861.3d0000000107068890T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA USA
| | - Jonathan Peters
- grid.133342.40000 0004 1936 9676Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA USA
| | - Weiqiang Xie
- grid.133342.40000 0004 1936 9676Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA USA
| | - Lin Chang
- grid.133342.40000 0004 1936 9676Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA USA
| | - Boqiang Shen
- grid.20861.3d0000000107068890T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA USA
| | - Heming Wang
- grid.20861.3d0000000107068890T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA USA
| | - Qi-Fan Yang
- grid.20861.3d0000000107068890T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA USA
| | - David Kinghorn
- grid.133342.40000 0004 1936 9676Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA USA ,Pro Precision Process and Reliability LLC, Carpinteria, CA USA
| | | | - Kerry J. Vahala
- grid.20861.3d0000000107068890T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA USA
| | | | - John E. Bowers
- grid.133342.40000 0004 1936 9676Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA USA
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20
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Li B, Jin W, Wu L, Chang L, Wang H, Shen B, Yuan Z, Feshali A, Paniccia M, Vahala KJ, Bowers JE. Reaching fiber-laser coherence in integrated photonics. Opt Lett 2021; 46:5201-5204. [PMID: 34653151 DOI: 10.1364/ol.439720] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 09/26/2021] [Indexed: 06/13/2023]
Abstract
We self-injection-lock a diode laser to a 1.41 m long, ultra-high Q integrated resonator. The hybrid integrated laser reaches a frequency noise floor of 0.006Hz2/Hz at 4 MHz offset, corresponding to a Lorentzian linewidth below 40 mHz-a record among semiconductor lasers. It also exhibits exceptional stability at low-offset frequencies, with frequency noise of 200Hz2/Hz at 100 Hz offset. Such performance, realized in a system comprised entirely of integrated photonic chips, marks a milestone in the development of integrated photonics; and, for the first time, to the best of our knowledge, exceeds the frequency noise performance of commercially available, high-performance fiber lasers.
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21
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Qin L, Hu Y, Wang J, Wang X, Zhao R, Shan H, Li K, Xu P, Wu H, Yan X, Liu L, Yi X, Wanke S, Bowers JE, Leebens-Mack JH, dePamphilis CW, Soltis PS, Soltis DE, Kong H, Jiao Y. Insights into angiosperm evolution, floral development and chemical biosynthesis from the Aristolochia fimbriata genome. Nat Plants 2021; 7:1239-1253. [PMID: 34475528 PMCID: PMC8445822 DOI: 10.1038/s41477-021-00990-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 07/22/2021] [Indexed: 05/04/2023]
Abstract
Aristolochia, a genus in the magnoliid order Piperales, has been famous for centuries for its highly specialized flowers and wide medicinal applications. Here, we present a new, high-quality genome sequence of Aristolochia fimbriata, a species that, similar to Amborella trichopoda, lacks further whole-genome duplications since the origin of extant angiosperms. As such, the A. fimbriata genome is an excellent reference for inferences of angiosperm genome evolution, enabling detection of two novel whole-genome duplications in Piperales and dating of previously reported whole-genome duplications in other magnoliids. Genomic comparisons between A. fimbriata and other angiosperms facilitated the identification of ancient genomic rearrangements suggesting the placement of magnoliids as sister to monocots, whereas phylogenetic inferences based on sequence data we compiled yielded ambiguous relationships. By identifying associated homologues and investigating their evolutionary histories and expression patterns, we revealed highly conserved floral developmental genes and their distinct downstream regulatory network that may contribute to the complex flower morphology in A. fimbriata. Finally, we elucidated the genetic basis underlying the biosynthesis of terpenoids and aristolochic acids in A. fimbriata.
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Affiliation(s)
- Liuyu Qin
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yiheng Hu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jinpeng Wang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
- School of Life Sciences and Center for Genomics and Computational Biology, North China University of Science and Technology, Tangshan, China
| | - Xiaoliang Wang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ran Zhao
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
| | - Hongyan Shan
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
| | - Kunpeng Li
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Peng Xu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hanying Wu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
| | - Xueqing Yan
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Lumei Liu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xin Yi
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
| | - Stefan Wanke
- Institute of Botany, Dresden University of Technology, Dresden, Germany
| | - John E Bowers
- Department of Plant Biology, University of Georgia, Athens, GA, USA
- Plant Genome Mapping Laboratory, University of Georgia, Athens, GA, USA
| | | | - Claude W dePamphilis
- Department of Biology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA
| | - Pamela S Soltis
- Florida Museum of Natural History, University of Florida, Gainesville, FL, USA
| | - Douglas E Soltis
- Florida Museum of Natural History, University of Florida, Gainesville, FL, USA
- Department of Biology, University of Florida, Gainesville, FL, USA
| | - Hongzhi Kong
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yuannian Jiao
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, Beijing, China.
- University of Chinese Academy of Sciences, Beijing, China.
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22
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Xiang C, Liu J, Guo J, Chang L, Wang RN, Weng W, Peters J, Xie W, Zhang Z, Riemensberger J, Selvidge J, Kippenberg TJ, Bowers JE. Laser soliton microcombs heterogeneously integrated on silicon. Science 2021; 373:99-103. [PMID: 34210884 DOI: 10.1126/science.abh2076] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 05/20/2021] [Indexed: 12/22/2022]
Abstract
Silicon photonics enables wafer-scale integration of optical functionalities on chip. Silicon-based laser frequency combs can provide integrated sources of mutually coherent laser lines for terabit-per-second transceivers, parallel coherent light detection and ranging, or photonics-assisted signal processing. We report heterogeneously integrated laser soliton microcombs combining both indium phospide/silicon (InP/Si) semiconductor lasers and ultralow-loss silicon nitride (Si3N4) microresonators on a monolithic silicon substrate. Thousands of devices can be produced from a single wafer by using complementary metal-oxide-semiconductor-compatible techniques. With on-chip electrical control of the laser-microresonator relative optical phase, these devices can output single-soliton microcombs with a 100-gigahertz repetition rate. Furthermore, we observe laser frequency noise reduction due to self-injection locking of the InP/Si laser to the Si3N4 microresonator. Our approach provides a route for large-volume, low-cost manufacturing of narrow-linewidth, chip-based frequency combs for next-generation high-capacity transceivers, data centers, space and mobile platforms.
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Affiliation(s)
- Chao Xiang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Junqiu Liu
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Joel Guo
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Lin Chang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Rui Ning Wang
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Wenle Weng
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Jonathan Peters
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Weiqiang Xie
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Zeyu Zhang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Johann Riemensberger
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Jennifer Selvidge
- Materials Department, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Tobias J Kippenberg
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
| | - John E Bowers
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, USA. .,Materials Department, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
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23
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Abstract
Polyploidy is ubiquitous and often recursive in plant lineages, most frequently resulting in extinction but occasionally associated with great evolutionary success. However, instead of chromosome numbers exponentially increasing due to recurrent polyploidy, most angiosperm species have fewer than 14 chromosome pairs. Following genome duplication, diploidisation can render one copy of essential genes nonfunctional without fitness cost. In isolated subpopulations, alternate (homoeologous) gene copies can be lost, creating incompatibilities that reduce fitness of hybrids between subpopulations, constraining exchange of favourable genetic changes and reducing species fitness. When multiple sets of incompatible genes are genetically linked, their deleterious effects are not independent. The effective number of independently acting sets of incompatible loci in hybrids is limited by chromosome number and recombination. Therefore, species with many chromosomes are subject to a higher fitness penalty during diploidisation. Karyotypic changes, especially fusions, that reduce gene flow are normally fitness disadvantages, but during the diploidisation process, can increase fitness by reducing mixing of differentially diploidised alleles. Fitness penalties caused by diploidisation favour accelerated karyotypic change, with each change increasing barriers to gene flow, contributing to speciation. Lower chromosome numbers and increased chromosome fusions confer advantages to surviving the diploidisation process following polyploid formation, by independent mechanisms.
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Affiliation(s)
- John E Bowers
- Plant Genome Mapping Laboratory, University of Georgia, Athens, GA, 30602, USA
| | - Andrew H Paterson
- Plant Genome Mapping Laboratory, University of Georgia, Athens, GA, 30602, USA
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24
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Jin W, Feshali A, Paniccia M, Bowers JE. Seamless multi-reticle photonics. Opt Lett 2021; 46:2984-2987. [PMID: 34129590 DOI: 10.1364/ol.427289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 05/26/2021] [Indexed: 06/12/2023]
Abstract
While Moore's law predicted shrinking transistors would enable exponential scaling of electronic circuits, the footprint of photonic components is limited by the wavelength of light. Thus, future high-complexity photonic integrated circuits (PICs) such as petabit-per-second transceivers, thousand-channel switches, and photonic quantum computers will require more area than a single reticle provides. In our novel approach, we overlay and widen waveguides in adjacent reticles to stitch a smooth transition between misaligned exposures. In SiN waveguides, we measure ultralow loss of 0.0004 dB per stitch, and produce a stitched delay line 23 m in length. We extend the design to silicon channel waveguides, and predict 50-fold lower loss or 50-fold smaller footprint versus a multimode-waveguide-based method. Our approach enables large-scale PICs to scale seamlessly beyond the single-reticle limit.
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25
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Boes A, Nguyen TG, Chang L, Bowers JE, Ren G, Mitchell A. Integrated photonic high extinction short and long pass filters based on lateral leakage. Opt Express 2021; 29:18905-18914. [PMID: 34154136 DOI: 10.1364/oe.426442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 05/24/2021] [Indexed: 06/13/2023]
Abstract
In this contribution we present a new approach to achieve high extinction short and long pass wavelength filters in the integrated photonic platform of lithium niobate on insulator. The filtering of unwanted wavelengths is achieved by employing lateral leakage and is related to the bound state in the continuum phenomenon. We show that it is possible to control the filter edge wavelength by adjusting the waveguide dimensions and that an extinction of hundreds of dB/cm is readily achievable. This enabled us to design a pump wavelength suppression of more than 100 dB in a 3.5 mm long waveguide, which is essential for on-chip integration of quantum-correlated photon pair sources. These findings pave the way to integrate multi wavelength experiments on chip for the next generation of photonic integrated circuits.
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26
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Steindl P, Snijders H, Westra G, Hissink E, Iakovlev K, Polla S, Frey JA, Norman J, Gossard AC, Bowers JE, Bouwmeester D, Löffler W. Artificial Coherent States of Light by Multiphoton Interference in a Single-Photon Stream. Phys Rev Lett 2021; 126:143601. [PMID: 33891441 DOI: 10.1103/physrevlett.126.143601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 03/05/2021] [Indexed: 06/12/2023]
Abstract
Coherent optical states consist of a quantum superposition of different photon number (Fock) states, but because they do not form an orthogonal basis, no photon number states can be obtained from it by linear optics. Here we demonstrate the reverse, by manipulating a random continuous single-photon stream using quantum interference in an optical Sagnac loop, we create engineered quantum states of light with tunable photon statistics, including approximate weak coherent states. We demonstrate this experimentally using a true single-photon stream produced by a semiconductor quantum dot in an optical microcavity, and show that we can obtain light with g^{(2)}(0)→1 in agreement with our theory, which can only be explained by quantum interference of at least 3 photons. The produced artificial light states are, however, much more complex than coherent states, containing quantum entanglement of photons, making them a resource for multiphoton entanglement.
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Affiliation(s)
- P Steindl
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, Netherlands
| | - H Snijders
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, Netherlands
| | - G Westra
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, Netherlands
| | - E Hissink
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, Netherlands
| | - K Iakovlev
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, Netherlands
| | - S Polla
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, Netherlands
| | - J A Frey
- Department of Physics, University of California, Santa Barbara, California 93106, USA
| | - J Norman
- Department of Electrical & Computer Engineering, University of California, Santa Barbara, California 93106, USA
| | - A C Gossard
- Department of Electrical & Computer Engineering, University of California, Santa Barbara, California 93106, USA
| | - J E Bowers
- Department of Electrical & Computer Engineering, University of California, Santa Barbara, California 93106, USA
| | - D Bouwmeester
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, Netherlands
- Department of Physics, University of California, Santa Barbara, California 93106, USA
| | - W Löffler
- Huygens-Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, Netherlands
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27
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Wan Y, Norman J, Liu S, Liu A, Bowers JE. Quantum Dot Lasers and Amplifiers on Silicon: Recent Advances and Future Developments. IEEE Nanotechnology Mag 2021. [DOI: 10.1109/mnano.2020.3048094] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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28
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Chang L, Xie W, Shu H, Yang QF, Shen B, Boes A, Peters JD, Jin W, Xiang C, Liu S, Moille G, Yu SP, Wang X, Srinivasan K, Papp SB, Vahala K, Bowers JE. Author Correction: Ultra-efficient frequency comb generation in AlGaAs-on-insulator microresonators. Nat Commun 2021; 12:1803. [PMID: 33727533 PMCID: PMC7966803 DOI: 10.1038/s41467-021-22031-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Lin Chang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA
| | - Weiqiang Xie
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA.
| | - Haowen Shu
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA.,State Key Laboratory of Advanced Optical Communications System and Networks, Peking University, Beijing, 100871, China
| | - Qi-Fan Yang
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Boqiang Shen
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Andreas Boes
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA.,School of Engineering, RMIT University, Melbourne, VIC, 3000, Australia
| | - Jon D Peters
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA
| | - Warren Jin
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA
| | - Chao Xiang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA
| | - Songtao Liu
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA
| | - Gregory Moille
- Microsystems and Nanotechnology Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Su-Peng Yu
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO, 80305, USA
| | - Xingjun Wang
- State Key Laboratory of Advanced Optical Communications System and Networks, Peking University, Beijing, 100871, China
| | - Kartik Srinivasan
- Microsystems and Nanotechnology Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Scott B Papp
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO, 80305, USA
| | - Kerry Vahala
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, 91125, USA
| | - John E Bowers
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA.
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29
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Khope ASP, Helkey R, Liu S, Khope S, Alferness RC, Saleh AAM, Bowers JE. Scalable multicast hybrid broadband-crossbar wavelength selective switch: proposal and analysis. Opt Lett 2021; 46:448-451. [PMID: 33449050 DOI: 10.1364/ol.412242] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 12/08/2020] [Indexed: 06/12/2023]
Abstract
In this Letter, we present a new hybrid broadband-crossbar switching network that can switch multiple wavelengths on demand and can also multicast. This switch fabric is an improvement over our previous design in both switch footprint and power consumption, as it reduces the number of switching elements by approximately 50%. We compare the switch loss and crosstalk with that of a multiwavelength selective crossbar switch. We also comment on fabrication tolerance of second-order ring resonators based on experimental results of 64 second-order ring resonators, and more than 250 heaters.
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30
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31
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Xie W, Chang L, Shu H, Norman JC, Peters JD, Wang X, Bowers JE. Ultrahigh-Q AlGaAs-on-insulator microresonators for integrated nonlinear photonics. Opt Express 2020; 28:32894-32906. [PMID: 33114964 DOI: 10.1364/oe.405343] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 10/06/2020] [Indexed: 06/11/2023]
Abstract
Aluminum gallium arsenide (AlGaAs) and related III-V semiconductors have excellent optoelectronic properties. They also possess strong material nonlinearity as well as high refractive indices. In view of these properties, AlGaAs is a promising candidate for integrated photonics, including both linear and nonlinear devices, passive and active devices, and associated applications. Low propagation loss is essential for integrated photonics, particularly in nonlinear applications. However, achieving low-loss and high-confinement AlGaAs photonic integrated circuits poses a challenge. Here we show an effective reduction of surface-roughness-induced scattering loss in fully etched high-confinement AlGaAs-on-insulator nanowaveguides by using a heterogeneous wafer-bonding approach and optimizing fabrication techniques. We demonstrate ultrahigh-quality AlGaAs microring resonators and realize quality factors up to 3.52 × 106 and finesses as high as 1.4 × 104. We also show ultra-efficient frequency comb generations in those resonators and achieve record-low threshold powers on the order of ∼20 µW and ∼120 µW for the resonators with 1 THz and 90 GHz free-spectral ranges, respectively. Our result paves the way for the implementation of AlGaAs as a novel integrated material platform specifically for nonlinear photonics and opens a new window for chip-based efficiency-demanding practical applications.
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32
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Khope ASP, Liu S, Zhang Z, Netherton AM, Hwang RL, Wissing A, Perez J, Tang F, Schow C, Helkey R, Alferness RC, Saleh AAM, Bowers JE. 2 λ switch. Opt Lett 2020; 45:5340-5343. [PMID: 33001889 DOI: 10.1364/ol.402241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 08/08/2020] [Indexed: 06/11/2023]
Abstract
We demonstrate an elastic multi-wavelength selective switch with up to two wavelength switching capability per crosspoint. We fabricated the switch in a silicon photonics foundry and demonstrated a 17 nm tuning range for ring resonators, with a mean path loss of 2.43 dB. This is a 70% reduction in path loss as compared to previous generations, and we demonstrate a high-speed pulse-amplitude-modulation-4 transmission at 111 Gbps through different paths of the switch.
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33
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Dong B, de Labriolle XC, Liu S, Dumont M, Huang H, Duan J, Norman JC, Bowers JE, Grillot F. 1.3-µm passively mode-locked quantum dot lasers epitaxially grown on silicon: gain properties and optical feedback stabilization. J Phys Photonics 2020. [DOI: 10.1088/2515-7647/aba5a6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
This work reports on an investigation of the optical feedback in an InAs/InGaAs passively mode-locked quantum dot (QD) laser epitaxially grown on silicon. Under the stably-resonant optical feedback condition, experiments demonstrate that the radio-frequency linewidth is narrowed whatever the bias voltage applied on the saturable absorber (SA) is; on the other hand, the effective linewidth enhancement factor of the device increases with the reverse bias voltage on the SA, hence it is observed that such an increase influences the mode-locking dynamic and the stability of device under optical feedback. This work gives insights for stabilizing epitaxial QD mode-locked lasers on silicon which is meaningful for their applications in future large-scale silicon electronic and photonic applications requiring low power consumption as well as for high-speed photonic analog-to-digital conversion, intrachip/interchip optical clock distribution and recovery.
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34
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Stern L, Zhang W, Chang L, Guo J, Xiang C, Tran MA, Huang D, Peters JD, Kinghorn D, Bowers JE, Papp SB. Ultra-precise optical-frequency stabilization with heterogeneous III-V/Si lasers. Opt Lett 2020; 45:5275-5278. [PMID: 32932510 DOI: 10.1364/ol.398845] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 07/02/2020] [Indexed: 06/11/2023]
Abstract
The demand for low-noise, continuous-wave, frequency-tunable lasers based on semiconductor integrated photonics has advanced in support of numerous applications. In particular, an important goal is to achieve a narrow spectral linewidth, commensurate with bulk-optic or fiber-optic laser platforms. Here we report on laser-frequency-stabilization experiments with a heterogeneously integrated III/V-Si widely tunable laser and a high-finesse, thermal-noise-limited photonic resonator. This hybrid architecture offers a chip-scale optical-frequency reference with an integrated linewidth of 60 Hz and a fractional frequency stability of 2.5×10-13 at 1 s integration time. We explore the potential for stabilization with respect to a resonator with lower thermal noise by characterizing laser-noise contributions such as residual amplitude modulation and photodetection noise. Widely tunable, compact and integrated, cost-effective, stable, and narrow-linewidth lasers are envisioned for use in various fields, including communication, spectroscopy, and metrology.
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35
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Duan J, Zhou Y, Dong B, Huang H, Norman JC, Jung D, Zhang Z, Wang C, Bowers JE, Grillot F. Effect of p-doping on the intensity noise of epitaxial quantum dot lasers on silicon. Opt Lett 2020; 45:4887-4890. [PMID: 32870883 DOI: 10.1364/ol.395499] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 08/03/2020] [Indexed: 06/11/2023]
Abstract
This work experimentally investigates the impact of p-doping on the relative intensity noise (RIN) properties and subsequently on the modulation properties of semiconductor quantum dot (QD) lasers epitaxially grown on silicon. Owing to the low threading dislocation density and the p-modulation doped GaAs barrier layer in the active region, the RIN level is found very stable with temperature with a minimum value of -150dB/Hz. The dynamical features extracted from the RIN spectra show that p-doping between zero and 20 holes/dot strongly modifies the modulation properties and gain nonlinearities through increased internal losses in the active region and thereby hinders the maximum achievable bandwidth. Overall, this Letter is important for designing future high-speed and low-noise QD devices integrated in future photonic integrated circuits.
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36
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Qin J, Shu H, Chang L, Xie W, Tao Y, Jin M, Wang X, Bowers JE. On-chip high-efficiency wavelength multicasting of PAM3/PAM4 signals using low-loss AlGaAs-on-insulator nanowaveguides. Opt Lett 2020; 45:4539-4542. [PMID: 32797003 DOI: 10.1364/ol.398777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 07/10/2020] [Indexed: 06/11/2023]
Abstract
Nonlinear optics-based optical signal processing (OSP) could potentially increase network flexibility because of its transparency, tunability, and large bandwidth. A low-loss, high nonlinearity, and compact integrated material platform is always the pursuit of OSP. In this Letter, a high-efficiency, one-to-six wavelength multicasting of 10 Gbaud pulse-amplitude modulation (PAM3/PAM4) signals using a 6 cm long Al0.2Ga0.8As-on-insulator nanowaveguide is experimentally demonstrated for the first time, to the best of our knowledge. The low-loss, combined with the high nonlinear coefficient of the AlGaAsOI platform, enables us to achieve -11.2dB average conversion efficiency clear eye diagrams and <2.1dB power penalty at KP4-forward error correction threshold (2.4×10-4) for all the output PAM3/PAM4 multicasting channels. This result points to a new generation of nonlinear OSP photonic integrated circuits.
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Malik A, Spott A, Wang Y, Stanton EJ, Peters J, Bowers JE. High resolution, high channel count mid-infrared arrayed waveguide gratings in silicon. Opt Lett 2020; 45:4551-4554. [PMID: 32797007 DOI: 10.1364/ol.397135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/16/2020] [Indexed: 06/11/2023]
Abstract
Arrayed waveguide gratings (AWGs) working in the 4.7 µm wavelength range are reported on silicon-on-insulator waveguides with 1500 nm thick silicon and 2 µm thick buried oxide layers. For eight channel devices, three different channel spacings (200 GHz, 100 GHz, and 50 GHz) with cross talk levels of -32.31dB, -31.87dB, and -27.28dB and insertion loss levels of -1.43dB, -4.2dB, and -2.3dB, respectively, are demonstrated. Fourteen channel AWGs with 170 GHz channel spacing and 16 channel AWGs with 87 GHz channel spacing are shown to have a cross talk value of -21.67dB and -24.30dB and insertion loss value of -4.2dB and -3.8dB, respectively. Two AWGs with 10 nm difference in channel peak are designed, and the measurements show a 9.3 nm difference. The transmission spectrum shift as a function of temperature is found to be 0.22 nm/°C.
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Chow YC, Lee C, Wong MS, Wu YR, Nakamura S, DenBaars SP, Bowers JE, Speck JS. Dependence of carrier escape lifetimes on quantum barrier thickness in InGaN/GaN multiple quantum well photodetectors. Opt Express 2020; 28:23796-23805. [PMID: 32752371 DOI: 10.1364/oe.399924] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 07/11/2020] [Indexed: 06/11/2023]
Abstract
We reported significant improvements in device speed by reducing the quantum barrier (QB) thicknesses in the InGaN/GaN multiple quantum well (MQW) photodetectors (PDs). A 3-dB bandwidth of 700 MHz was achieved with a reverse bias of -6 V. Carrier escape lifetimes due to carrier trapping in the quantum wells (QWs) were obtained from both simulation and experimental fitting, identifying carrier trapping as the major speed limiting factor in the InGaN/GaN MQW PDs.
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Xiang C, Jin W, Guo J, Williams C, Netherton AM, Chang L, Morton PA, Bowers JE. Effects of nonlinear loss in high-Q Si ring resonators for narrow-linewidth III-V/Si heterogeneously integrated tunable lasers. Opt Express 2020; 28:19926-19936. [PMID: 32680062 DOI: 10.1364/oe.394491] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 06/05/2020] [Indexed: 06/11/2023]
Abstract
High-Q Si ring resonators play an important role in the development of widely tunable heterogeneously integrated lasers. However, while a high Q-factor (Q > 1 million) is important for ring resonators in a laser cavity, the parasitic high-power density in a Si resonator can deteriorate the laser performance at high power levels due to nonlinear loss. Here, we experimentally show that this detrimental effect can happen at moderate power levels (a few milliwatts) where typical heterogeneously integrated lasers work. We further compare different ring resonators, including extended Si ring resonators and Si3N4 ring resonators and provide practical approaches to minimize this effect. Our results provide explanations and guidelines for high-Q ring resonator designs in heterogeneously integrated tunable lasers, and they are also applicable for hybrid integrated butt-coupled lasers.
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Jin W, John DD, Bauters JF, Bosch T, Thibeault BJ, Bowers JE. Deuterated silicon dioxide for heterogeneous integration of ultra-low-loss waveguides. Opt Lett 2020; 45:3340-3343. [PMID: 32538978 DOI: 10.1364/ol.394121] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 05/01/2020] [Indexed: 06/11/2023]
Abstract
Ultra-low-loss waveguide fabrication typically requires high-temperature annealing beyond 1000°C to reduce the hydrogen content in deposited dielectric films. However, realizing the full potential of an ultra-low loss will require the integration of active materials that cannot tolerate high temperature. Uniting ultra-low-loss waveguides with on-chip sources, modulators, and detectors will require a low-temperature, low-loss dielectric to serve as a passivation and spacer layers for complex fabrication processes. We report a 250°C deuterated silicon dioxide film for top cladding in ultra-low-loss waveguides. Using multiple techniques, we measure propagation loss below 12 dB/m for the entire 1200-1650 nm range and top-cladding material absorption below 1 dB/m in the S, C, and L bands.
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41
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Li C, Zhang M, Bowers JE, Dai D. Ultra-broadband polarization beam splitter with silicon subwavelength-grating waveguides. Opt Lett 2020; 45:2259-2262. [PMID: 32287208 DOI: 10.1364/ol.389207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 03/10/2020] [Indexed: 06/11/2023]
Abstract
An ultra-broadband polarization beam splitter (PBS) with low excess loss (EL) and a high extinction ratio (ER) is proposed and demonstrated for the case with 340 nm thick silicon-on-insulator waveguides. Here the PBS is realized by using cascaded adiabatic dual-core tapers, which consist of a strip core and a subwavelength-grating core. For the designed PBS, which has a 33.6 µm long mode-evolution region, the ELs are ${ \lt }{0.3}\;{\rm dB}$<0.3dB, and the ERs are ${ \gt }{20}\;{\rm dB}$>20dB for both TE and TM polarizations in an ultra-broad bandwidth of ${ \gt }{270}\;{\rm nm}$>270nm (1400-1670 nm) in theory. For the fabricated PBS, the measured bandwidths for achieving ERs of ${\sim}{20}$∼20 and ${\sim}{25}\;{\rm dB}$∼25dB are 240 and 220 nm, while the 1 dB bandwidth is as large as 230 nm, which are the largest bandwidths reported to date, to the best of our knowledge.
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Stanton EJ, Chiles J, Nader N, Moody G, Volet N, Chang L, Bowers JE, Woo Nam S, Mirin RP. Efficient second harmonic generation in nanophotonic GaAs-on-insulator waveguides. Opt Express 2020; 28:9521-9532. [PMID: 32225558 DOI: 10.1364/oe.389423] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 03/05/2020] [Indexed: 06/10/2023]
Abstract
Nonlinear frequency conversion plays a crucial role in advancing the functionality of next-generation optical systems. Portable metrology references and quantum networks will demand highly efficient second-order nonlinear devices, and the intense nonlinear interactions of nanophotonic waveguides can be leveraged to meet these requirements. Here we demonstrate second harmonic generation (SHG) in GaAs-on-insulator waveguides with unprecedented efficiency of 40 W-1 for a single-pass device. This result is achieved by minimizing the propagation loss and optimizing phase-matching. We investigate surface-state absorption and design the waveguide geometry for modal phase-matching with tolerance to fabrication variation. A 2.0 µm pump is converted to a 1.0 µm signal in a length of 2.9 mm with a wide signal bandwidth of 148 GHz. Tunable and efficient operation is demonstrated over a temperature range of 45 °C with a slope of 0.24 nm/°C. Wafer-bonding between GaAs and SiO2 is optimized to minimize waveguide loss, and the devices are fabricated on 76 mm wafers with high uniformity. We expect this device to enable fully integrated self-referenced frequency combs and high-rate entangled photon pair generation.
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Wan Y, Shang C, Huang J, Xie Z, Jain A, Norman J, Chen B, Gossard AC, Bowers JE. Low Dark Current 1.55 Micrometer InAs Quantum Dash Waveguide Photodiodes. ACS Nano 2020; 14:3519-3527. [PMID: 32083840 DOI: 10.1021/acsnano.9b09715] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Photodiodes and integrated optical receivers operating at 1.55 micrometer (μm) wavelength are crucial for long-haul communication and data transfer systems. In this paper, we report C-band InAs quantum dash (Qdash) waveguide photodiodes (PDs) with a record-low dark current of 5 pA, a responsivity of 0.26 A/W at 1.55 μm, and open eye diagrams up to 10 Gb/s. These Qdash-based PDs leverage the same epitaxial layers and processing steps as Qdash lasers and can thus be integrated with laser sources for power monitors or amplifiers for preamplified receivers, manifesting themselves as a promising alternative to their InGaAs and Ge counterparts in low-power optical communication links.
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Affiliation(s)
- Yating Wan
- Institute for Energy Efficiency, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Chen Shang
- Materials Department, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Jian Huang
- School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Zhiyang Xie
- School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Aditya Jain
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Justin Norman
- Materials Department, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Baile Chen
- Institute for Energy Efficiency, University of California Santa Barbara, Santa Barbara, California 93106, United States
- School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Arthur C Gossard
- Institute for Energy Efficiency, University of California Santa Barbara, Santa Barbara, California 93106, United States
- Materials Department, University of California Santa Barbara, Santa Barbara, California 93106, United States
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - John E Bowers
- Institute for Energy Efficiency, University of California Santa Barbara, Santa Barbara, California 93106, United States
- Materials Department, University of California Santa Barbara, Santa Barbara, California 93106, United States
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, California 93106, United States
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Chang L, Xie W, Shu H, Yang QF, Shen B, Boes A, Peters JD, Jin W, Xiang C, Liu S, Moille G, Yu SP, Wang X, Srinivasan K, Papp SB, Vahala K, Bowers JE. Ultra-efficient frequency comb generation in AlGaAs-on-insulator microresonators. Nat Commun 2020; 11:1331. [PMID: 32165610 PMCID: PMC7067760 DOI: 10.1038/s41467-020-15005-5] [Citation(s) in RCA: 94] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 02/10/2020] [Indexed: 12/04/2022] Open
Abstract
Recent advances in nonlinear optics have revolutionized integrated photonics, providing on-chip solutions to a wide range of new applications. Currently, state of the art integrated nonlinear photonic devices are mainly based on dielectric material platforms, such as Si3N4 and SiO2. While semiconductor materials feature much higher nonlinear coefficients and convenience in active integration, they have suffered from high waveguide losses that prevent the realization of efficient nonlinear processes on-chip. Here, we challenge this status quo and demonstrate a low loss AlGaAs-on-insulator platform with anomalous dispersion and quality (Q) factors beyond 1.5 × 106. Such a high quality factor, combined with high nonlinear coefficient and small mode volume, enabled us to demonstrate a Kerr frequency comb threshold of only ∼36 µW in a resonator with a 1 THz free spectral range, ∼100 times lower compared to that in previous semiconductor platforms. Moreover, combs with broad spans (>250 nm) have been generated with a pump power of ∼300 µW, which is lower than the threshold power of state-of the-art dielectric micro combs. A soliton-step transition has also been observed for the first time in an AlGaAs resonator. Despite larger nonlinear coefficients, waveguide losses have prevented using semiconductors instead of dielectric materials for on-chip frequency-comb sources. By significantly reducing waveguide loss, ultra-low-threshold Kerr comb generation is demonstrated in a high-Q AlGaAs-on-insulator microresonator system.
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Affiliation(s)
- Lin Chang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA
| | - Weiqiang Xie
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA.
| | - Haowen Shu
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA.,State Key Laboratory of Advanced Optical Communications System and Networks, Peking University, Beijing, 100871, China
| | - Qi-Fan Yang
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Boqiang Shen
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Andreas Boes
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA.,School of Engineering, RMIT University, Melbourne, VIC, 3000, Australia
| | - Jon D Peters
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA
| | - Warren Jin
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA
| | - Chao Xiang
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA
| | - Songtao Liu
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA
| | - Gregory Moille
- Microsystems and Nanotechnology Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Su-Peng Yu
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO, 80305, USA
| | - Xingjun Wang
- State Key Laboratory of Advanced Optical Communications System and Networks, Peking University, Beijing, 100871, China
| | - Kartik Srinivasan
- Microsystems and Nanotechnology Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Scott B Papp
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO, 80305, USA
| | - Kerry Vahala
- T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, CA, 91125, USA
| | - John E Bowers
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, 93106, USA.
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Chow WW, Liu S, Zhang Z, Bowers JE, Sargent M. Multimode description of self-mode locking in a single-section quantum-dot laser. Opt Express 2020; 28:5317-5330. [PMID: 32121755 DOI: 10.1364/oe.382821] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 01/19/2020] [Indexed: 06/10/2023]
Abstract
This paper describes a theory for mode locking and frequency comb generation by four-wave mixing in a semiconductor quantum-dot active medium. The derivation uses a multimode semiclassical laser theory that accounts for fast carrier collisions within an inhomogeneous distribution of quantum dots. Numerical simulations are presented to illustrate the role of active medium nonlinearities in mode competition, gain saturation, carrier-induced refractive index and creation of combination tones that lead to locking of beat frequencies among lasing modes in the presence of cavity material dispersion.
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46
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Boes A, Chang L, Knoerzer M, Nguyen TG, Peters JD, Bowers JE, Mitchell A. Improved second harmonic performance in periodically poled LNOI waveguides through engineering of lateral leakage. Opt Express 2019; 27:23919-23928. [PMID: 31510289 DOI: 10.1364/oe.27.023919] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 07/29/2019] [Indexed: 06/10/2023]
Abstract
In this contribution, we investigate the impact of lateral leakage for linear and nonlinear optical waveguides in lithium niobate on an insulator (LNOI). Silicon nitride (SiN) loaded and direct patterned lithium niobate cross-sections are investigated. We show that lateral leakage can take place for the TE mode in LNOI ridge waveguides (X-cut lithium niobate), due to the birefringence of the material. This work gives guidelines for designing waveguides in LNOI that do not suffer from the lateral leakage effect. By applying these design considerations, we avoided the lateral leakage effect at the second harmonic wavelength of a nonlinear optical waveguide in LNOI and demonstrate a peak second harmonic generation conversion efficiency of ~1160% W-1cm-2.
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Chang L, Boes A, Pintus P, Xie W, Peters JD, Kennedy MJ, Jin W, Guo XW, Yu SP, Papp SB, Bowers JE. Low loss (Al)GaAs on an insulator waveguide platform. Opt Lett 2019; 44:4075-4078. [PMID: 31415550 DOI: 10.1364/ol.44.004075] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 07/14/2019] [Indexed: 06/10/2023]
Abstract
In this Letter, we demonstrate a low loss gallium arsenide and aluminum gallium arsenide on an insulator platform by heterogenous integration. The resonators on this platform exhibit record high quality factors up to 1.5×106, corresponding to a propagation loss ∼0.4 dB/cm. For the first time, to the best of our knowledge, the loss of integrated III-V semiconductor on insulator waveguides becomes comparable with that of the silicon-on-insulator waveguides. This Letter should have a significant impact on photonic integrated circuits (PICs) and become an essential building block for the evolving nonlinear PICs and integrated quantum photonic systems in the future.
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Xiang C, Morton PA, Bowers JE. Ultra-narrow linewidth laser based on a semiconductor gain chip and extended Si 3N 4 Bragg grating. Opt Lett 2019; 44:3825-3828. [PMID: 31368975 DOI: 10.1364/ol.44.003825] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 06/30/2019] [Indexed: 06/10/2023]
Abstract
We demonstrate ultra-narrow linewidth fixed wavelength hybrid lasers composing a semiconductor gain chip and extended silicon nitride Bragg grating. Fabricated ultra-low κ Bragg gratings provide a narrow bandwidth and high side-lobe suppression ratio. A single-wavelength 1544 nm hybrid extended-distributed Bragg reflector laser with 24 mW output power and a Lorentzian linewidth of 320 Hz is demonstrated, providing a high-performance light source for on- and off-chip applications.
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49
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Yuan Y, Jung D, Sun K, Zheng J, Jones AH, Bowers JE, Campbell JC. III-V on silicon avalanche photodiodes by heteroepitaxy. Opt Lett 2019; 44:3538-3541. [PMID: 31305567 DOI: 10.1364/ol.44.003538] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 06/10/2019] [Indexed: 06/10/2023]
Abstract
We demonstrate a III-V avalanche photodiode (APD) grown by heteroepitaxy on silicon. This InGaAs/InAlAs APD exhibits low dark current, gain >20, external quantum efficiency >40%, and similar low excess noise, k∼0.2, as InAlAs APDs on InP.
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50
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Chew SX, Huang D, Li L, Song S, Tran MA, Yi X, Bowers JE. Integrated microwave photonic phase shifter with full tunable phase shifting range (> 360°) and RF power equalization. Opt Express 2019; 27:14798-14808. [PMID: 31163922 DOI: 10.1364/oe.27.014798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 04/15/2019] [Indexed: 06/09/2023]
Abstract
We report a novel microwave photonic phase and amplitude control structure based on a single microring resonator with a tunable Mach Zehnder interferometer reflective loop, which enables the realization of a continuously tunable microwave photonic phase shifter with enhanced phase tuning range while simultaneously compensating for the RF power variations. The complimentary tuning of the phase and amplitude presents a simplistic approach to resolve the inherent trade-off between maintaining a full RF phase shift while eliminating large RF power variations. Detailed simulations have been carried out to analyze the performance of the new structure as a microwave photonic phase shifter, where the reflective nature of the proposed configuration shows an effective doubling of the phase range while the amplitude compensation module provides a parallel control to potentially reduce the RF amplitude variations to virtually zero. The phase range enhancement, which is first verified experimentally with a passive only chip, demonstrates the capability to achieve a continuously tunable RF phase shift of 0-510° with an RF amplitude variation of 9 dB. Meanwhile, the amplitude compensation scheme is incorporated onto an active chip with a continuously tunable RF phase shift of 0-150°, where the RF power variations is shown to be reduced by 5 dB while maintaining a constant RF phase shift.
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