1
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Yu X, Weeber JC, Markey L, Arocas J, Bouhelier A, Leray A, Colas des Francs G. Nano antenna-assisted quantum dots emission into high-index planar waveguide. NANOTECHNOLOGY 2024; 35:265201. [PMID: 38522099 DOI: 10.1088/1361-6528/ad3742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 03/24/2024] [Indexed: 03/26/2024]
Abstract
Integrated quantum photonic circuits require the efficient coupling of photon sources to photonic waveguides. Hybrid plasmonic/photonic platforms are a promising approach, taking advantage of both plasmon modal confinement for efficient coupling to a nearby emitter and photonic circuitry for optical data transfer and processing. In this work, we established directional quantum dot (QD) emission coupling to a planar TiO2waveguide assisted by a Yagi-Uda antenna. Antenna on waveguide is first designed by scaling radio frequency dimensions to nano-optics, taking into account the hybrid plasmonic/photonic platform. Design is then optimized by full numerical simulations. We fabricate the antenna on a TiO2planar waveguide and deposit a few QDs close to the Yagi-Uda antenna. The optical characterization shows clear directional coupling originating from antenna effect. We estimate the coupling efficiency and directivity of the light emitted into the waveguide.
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Affiliation(s)
- X Yu
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), CNRS UMR 6303, Université de Bourgogne, BP 47870, F-21078 Dijon, France
| | - J-C Weeber
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), CNRS UMR 6303, Université de Bourgogne, BP 47870, F-21078 Dijon, France
| | - L Markey
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), CNRS UMR 6303, Université de Bourgogne, BP 47870, F-21078 Dijon, France
| | - J Arocas
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), CNRS UMR 6303, Université de Bourgogne, BP 47870, F-21078 Dijon, France
| | - A Bouhelier
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), CNRS UMR 6303, Université de Bourgogne, BP 47870, F-21078 Dijon, France
| | - A Leray
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), CNRS UMR 6303, Université de Bourgogne, BP 47870, F-21078 Dijon, France
| | - G Colas des Francs
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), CNRS UMR 6303, Université de Bourgogne, BP 47870, F-21078 Dijon, France
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2
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Farrahi T, Giakos GK. Next-Generation Reconfigurable Nanoantennas and Polarization of Light. MICROMACHINES 2023; 14:1132. [PMID: 37374717 DOI: 10.3390/mi14061132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 05/23/2023] [Accepted: 05/25/2023] [Indexed: 06/29/2023]
Abstract
This study is aimed at the design, calibration, and development of a near-infrared (NIR) liquid crystal multifunctional automated optical polarimeter, which is aimed at the study and characterization of the polarimetric properties of polymer optical nanofilms. The characterization of these novel nanophotonic structures has been achieved, in terms of Mueller matrix and Stokes parameter analyses. The nanophotonic structures of this study consisted of (a) a matrix consisting of two different polymer domains, namely polybutadiene (PB) and polystyrene (PS), functionalized with gold nanoparticles; (b) cast and annealed Poly (styrene-b-methyl methacrylate) (PS-PMMA) diblock copolymers; (c) a matrix of a block copolymer (BCP) domain, PS-b-PMMA or Poly (styrene-block-methy methacrylate), functionalized with gold nanoparticles; and (d) different thicknesses of PS-b-P2VP diblock copolymer functionalized with gold nanoparticles. In all cases, backscattered infrared light was studied and related to the polarization figures-of-merit (FOM). The outcome of this study indicates that functionalized polymer nanomaterials, depending upon their structure and composition, exhibit promising optical characteristics, modulating and manipulating the polarimetric properties of light. The fabrication of technologically useful, tunable, conjugated polymer blends with an optimized refractive index, shape, size, spatial orientation, and arrangement would lead to the development of new nanoantennas and metasurfaces.
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Affiliation(s)
- Tannaz Farrahi
- Department of Physics, University of Colorado, Colorado, CO 80302, USA
| | - George K Giakos
- Department of Electrical and Computer Engineering, Manhattan College, New York, NY 10463, USA
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3
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Lin Y, Che D, Hao W, Dong Y, Guo H, Wang J, Zhang X. Controllable Patterning of Metallic Photonic Crystals for Waveguide-Plasmon Interaction. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:629. [PMID: 36838997 PMCID: PMC9962536 DOI: 10.3390/nano13040629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 01/31/2023] [Accepted: 02/02/2023] [Indexed: 06/18/2023]
Abstract
Waveguide-plasmon polaritons sustained in metallic photonic crystal slabs show fascinating properties, such as narrow bandwidth and ultrafast dynamics crucial for biosensing, light emitting, and ultrafast switching. However, the patterning of metallic photonic crystals using electron beam lithography is challenging in terms of high efficiency, large area coverage, and cost control. This paper describes a controllable patterning technique for the fabrication of an Ag grating structure on an indium-tin oxide (ITO) slab that enables strong photon-plasmon interaction to obtain waveguide-plasmon polaritons. The Ag grating consisting of self-assembled silver nanoparticles (NPs) exhibits polarization-independent properties for the excitation of the hybrid waveguide-plasmon mode. The Ag NP grating can also be annealed at high temperature to form a continuous nanoline grating that supports the hybrid waveguide-plasmon mode only under transverse magnetic (TM) polarization. We tuned the morphology and the periodicity of the Ag grating through the concentration of silver salt and the photoresist template, respectively, to manipulate the strong coupling between the plasmon and the waveguide modes of different orders.
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Affiliation(s)
- Yuanhai Lin
- Liaoning Key Laboratory of Marine Sensing and Intelligent Detection, Dalian Maritime University, Dalian 116026, China
- Information Science and Technology College, Dalian Maritime University, Dalian 116026, China
| | - Deqing Che
- Liaoning Key Laboratory of Marine Sensing and Intelligent Detection, Dalian Maritime University, Dalian 116026, China
- Information Science and Technology College, Dalian Maritime University, Dalian 116026, China
| | - Wenjie Hao
- Liaoning Key Laboratory of Marine Sensing and Intelligent Detection, Dalian Maritime University, Dalian 116026, China
- Information Science and Technology College, Dalian Maritime University, Dalian 116026, China
| | - Yifei Dong
- Liaoning Key Laboratory of Marine Sensing and Intelligent Detection, Dalian Maritime University, Dalian 116026, China
- Information Science and Technology College, Dalian Maritime University, Dalian 116026, China
| | - Heng Guo
- Liaoning Key Laboratory of Marine Sensing and Intelligent Detection, Dalian Maritime University, Dalian 116026, China
- Information Science and Technology College, Dalian Maritime University, Dalian 116026, China
| | - Junsheng Wang
- Liaoning Key Laboratory of Marine Sensing and Intelligent Detection, Dalian Maritime University, Dalian 116026, China
- Information Science and Technology College, Dalian Maritime University, Dalian 116026, China
| | - Xinping Zhang
- Institute of Information Photonics Technology and College of Applied Sciences, Beijing University of Technology, Beijing 100124, China
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4
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Meng Y, Chen Y, Lu L, Ding Y, Cusano A, Fan JA, Hu Q, Wang K, Xie Z, Liu Z, Yang Y, Liu Q, Gong M, Xiao Q, Sun S, Zhang M, Yuan X, Ni X. Optical meta-waveguides for integrated photonics and beyond. LIGHT, SCIENCE & APPLICATIONS 2021; 10:235. [PMID: 34811345 PMCID: PMC8608813 DOI: 10.1038/s41377-021-00655-x] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 09/17/2021] [Accepted: 09/28/2021] [Indexed: 05/13/2023]
Abstract
The growing maturity of nanofabrication has ushered massive sophisticated optical structures available on a photonic chip. The integration of subwavelength-structured metasurfaces and metamaterials on the canonical building block of optical waveguides is gradually reshaping the landscape of photonic integrated circuits, giving rise to numerous meta-waveguides with unprecedented strength in controlling guided electromagnetic waves. Here, we review recent advances in meta-structured waveguides that synergize various functional subwavelength photonic architectures with diverse waveguide platforms, such as dielectric or plasmonic waveguides and optical fibers. Foundational results and representative applications are comprehensively summarized. Brief physical models with explicit design tutorials, either physical intuition-based design methods or computer algorithms-based inverse designs, are cataloged as well. We highlight how meta-optics can infuse new degrees of freedom to waveguide-based devices and systems, by enhancing light-matter interaction strength to drastically boost device performance, or offering a versatile designer media for manipulating light in nanoscale to enable novel functionalities. We further discuss current challenges and outline emerging opportunities of this vibrant field for various applications in photonic integrated circuits, biomedical sensing, artificial intelligence and beyond.
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Affiliation(s)
- Yuan Meng
- State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, 100084, Beijing, China
| | - Yizhen Chen
- Shanghai Engineering Research Center of Ultra-Precision Optical Manufacturing and School of Information, Science and Technology, Fudan University, Shanghai, 200433, China
| | - Longhui Lu
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Yimin Ding
- Department of Electrical Engineering, Pennsylvania State University, University Park, PA, 16802, USA
| | - Andrea Cusano
- Optoelectronic Division, Department of Engineering, University of Sannio, I-82100, Benevento, Italy
| | - Jonathan A Fan
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Qiaomu Hu
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Kaiyuan Wang
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Zhenwei Xie
- Nanophotonics Research Centre, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Shenzhen University, Shenzhen, 518060, China
| | - Zhoutian Liu
- State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, 100084, Beijing, China
| | - Yuanmu Yang
- State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, 100084, Beijing, China
| | - Qiang Liu
- State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, 100084, Beijing, China
- Key Laboratory of Photonic Control Technology, Ministry of Education, Tsinghua University, 100084, Beijing, China
| | - Mali Gong
- State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, 100084, Beijing, China
- Key Laboratory of Photonic Control Technology, Ministry of Education, Tsinghua University, 100084, Beijing, China
| | - Qirong Xiao
- State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, 100084, Beijing, China.
- Key Laboratory of Photonic Control Technology, Ministry of Education, Tsinghua University, 100084, Beijing, China.
| | - Shulin Sun
- Shanghai Engineering Research Center of Ultra-Precision Optical Manufacturing and School of Information, Science and Technology, Fudan University, Shanghai, 200433, China.
- Yiwu Research Institute of Fudan University, Chengbei Road, Yiwu City, 322000, Zhejiang, China.
| | - Minming Zhang
- School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China.
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China.
| | - Xiaocong Yuan
- Nanophotonics Research Centre, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Shenzhen University, Shenzhen, 518060, China
| | - Xingjie Ni
- Department of Electrical Engineering, Pennsylvania State University, University Park, PA, 16802, USA
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5
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Zhu Z, Yuan J, Jiang L. Multifunctional and multichannel all-optical logic gates based on the in-plane coherent control of localized surface plasmons. OPTICS LETTERS 2020; 45:6362-6365. [PMID: 33258812 DOI: 10.1364/ol.402085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 10/07/2020] [Indexed: 06/12/2023]
Abstract
In this Letter, we report a scheme to design multifunctional and multichannel all-optical logic gates based on the in-plane coherent control of localized surface plasmons in an Au nanorod (NR) array on the Si substrate. By using theoretical analysis and structural optimization, we numerically demonstrate a four-channel all-optical logic gate device that can switch three basic logic operations on each NR only by controlling the phase differences of incident beams. This device is ultra-compact in size and shows high extensibility for parallel logic operations, which may be applied in future high-speed on-chip integrated optical computing.
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6
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Doeleman HM, Dieleman CD, Mennes C, Ehrler B, Koenderink AF. Observation of Cooperative Purcell Enhancements in Antenna-Cavity Hybrids. ACS NANO 2020; 14:12027-12036. [PMID: 32870669 PMCID: PMC7513474 DOI: 10.1021/acsnano.0c05233] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 09/01/2020] [Indexed: 05/25/2023]
Abstract
Localizing light to nanoscale volumes through nanoscale resonators that are low loss and precisely tailored in spectrum to properties of matter is crucial for classical and quantum light sources, cavity QED, molecular spectroscopy, and many other applications. To date, two opposite strategies have been identified: to use either plasmonics with deep subwavelength confinement yet high loss and very poor spectral control or instead microcavities with exquisite quality factors yet poor confinement. In this work we realize hybrid plasmonic-photonic resonators that enhance the emission of single quantum dots, profiting from both plasmonic confinement and microcavity quality factors. Our experiments directly demonstrate how cavity and antenna jointly realize large cooperative Purcell enhancements through interferences. These can be controlled to engineer arbitrary Fano lineshapes in the local density of optical states.
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Affiliation(s)
- Hugo M. Doeleman
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, Netherlands
- Van
der Waals-Zeeman Instituut, Institute of Physics, Universiteit van Amsterdam, Science Park 904, Postbus 94485, 1090
GL Amsterdam, Netherlands
| | | | - Christiaan Mennes
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, Netherlands
| | - Bruno Ehrler
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, Netherlands
| | - A. Femius Koenderink
- Center
for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, Netherlands
- Van
der Waals-Zeeman Instituut, Institute of Physics, Universiteit van Amsterdam, Science Park 904, Postbus 94485, 1090
GL Amsterdam, Netherlands
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7
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Maccaferri N, Meuret S, Kornienko N, Jariwala D. Speeding up Nanoscience and Nanotechnology with Ultrafast Plasmonics. NANO LETTERS 2020; 20:5593-5596. [PMID: 32787183 DOI: 10.1021/acs.nanolett.0c02452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Surface plasmons are collective oscillations of free electrons at the interface between a conducting material and the dielectric environment. These excitations support the formation of strongly enhanced and confined electromagnetic fields. As well, they display fast dynamics lasting tens of femtoseconds and can lead to a strong nonlinear optical response at the nanoscale. Thus, they represent the perfect tool to drive and control fast optical processes, such as ultrafast optical switching, single photon emission, as well as strong coupling interactions to explore and tailor photochemical reactions. In this Virtual Issue, we gather several important papers published in Nano Letters in the past decade reporting studies on the ultrafast dynamics of surface plasmons.
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Affiliation(s)
- Nicolò Maccaferri
- Department of Physics and Materials Science, Université du Luxembourg, 162a avenue de la Faïencerie, L-1511, Luxembourg, Luxembourg
| | - Sophie Meuret
- CEMES, CNRS - UPR8011, Université de Toulouse, 31055 Toulouse, France
| | - Nikolay Kornienko
- Department of Chemistry, Université de Montréal, Roger-Gaudry Building, Montreal, Quebec H3C 3J7, Canada
| | - Deep Jariwala
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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8
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Bao Q, Li W, Xu P, Zhang M, Dai D, Wang P, Guo X, Tong L. On-chip single-mode CdS nanowire laser. LIGHT, SCIENCE & APPLICATIONS 2020; 9:42. [PMID: 32194956 PMCID: PMC7073330 DOI: 10.1038/s41377-020-0277-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 02/22/2020] [Accepted: 02/26/2020] [Indexed: 05/24/2023]
Abstract
By integrating a free-standing cadmium sulfide (CdS) nanowire onto a silicon nitride (SiN) photonic chip, we demonstrate a highly compact on-chip single-mode CdS nanowire laser. The mode selection is realized using a Mach-Zehnder interferometer (MZI) structure. When the pumping intensity exceeds the lasing threshold of 4.9 kW/cm2, on-chip single-mode lasing at ~518.9 nm is achieved with a linewidth of 0.1 nm and a side-mode suppression ratio of up to a factor of 20 (13 dB). The output of the nanowire laser is channelled into an on-chip SiN waveguide with high efficiency (up to 58%) by evanescent coupling, and the directional coupling ratio between the two output ports can be varied from 90 to 10% by predesigning the coupling length of the SiN waveguide. Our results open new opportunities for both nanowire photonic devices and on-chip light sources and may pave the way towards a new category of hybrid nanolasers for chip-integrated applications.
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Affiliation(s)
- Qingyang Bao
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310027 China
| | - Weijia Li
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310027 China
| | - Peizhen Xu
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310027 China
| | - Ming Zhang
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310027 China
| | - Daoxin Dai
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310027 China
| | - Pan Wang
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310027 China
| | - Xin Guo
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310027 China
| | - Limin Tong
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310027 China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006 China
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9
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Chen C, Mohr DA, Choi HK, Yoo D, Li M, Oh SH. Waveguide-Integrated Compact Plasmonic Resonators for On-Chip Mid-Infrared Laser Spectroscopy. NANO LETTERS 2018; 18:7601-7608. [PMID: 30216715 DOI: 10.1021/acs.nanolett.8b03156] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The integration of nanoplasmonic devices with a silicon photonic platform affords a new approach for efficient light delivery by combining the high field enhancement of plasmonics and the ultralow propagation loss of dielectric waveguides. Such a hybrid integration obviates the need for a bulky free-space optics setup and can lead to fully integrated, on-chip optical sensing systems. Here, we demonstrate ultracompact plasmonic resonators directly patterned atop a silicon waveguide for mid-infrared spectroscopic chemical sensing. The footprint of the plasmonic nanorod resonators is as small as 2 μm2, yet they can couple with the mid-infrared waveguide mode efficiently. The plasmonic resonance is directly measured through the transmission spectrum of the waveguide with a coupling efficiency greater than 70% and a field intensity enhancement factor of over 3600 relative to the evanescent waveguide field intensity. Using this hybrid device and a tunable mid-infrared laser source, surface-enhanced infrared absorption spectroscopy of both a thin poly(methyl methacrylate) film and an octadecanethiol monolayer is successfully demonstrated.
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Affiliation(s)
- Che Chen
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Daniel A Mohr
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Han-Kyu Choi
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Daehan Yoo
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Mo Li
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering , University of Minnesota , Minneapolis , Minnesota 55455 , United States
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10
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Chen B, Yu X, Chen X, Milosevic MM, Thomson DJ, Khokhar AZ, Saito S, Muskens OL, Reed GT. Real-time monitoring and gradient feedback enable accurate trimming of ion-implanted silicon photonic devices. OPTICS EXPRESS 2018; 26:24953-24963. [PMID: 30469603 DOI: 10.1364/oe.26.024953] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 08/11/2018] [Indexed: 06/09/2023]
Abstract
Fabrication errors pose significant challenges on silicon photonics, promoting post-fabrication trimming technologies to ensure device performance. Conventional approaches involve multiple trimming and characterization steps, impacting overall fabrication complexity. Here we demonstrate a highly accurate trimming method combining laser annealing of germanium implanted silicon waveguide and real-time monitoring of device performance. Direct feedback of the trimming process is facilitated by a differential spectroscopic technique based on photomodulation. The resonant wavelength trimming accuracy is better than 0.15 nm for ring resonators with 20-µm radius. We also realize operating point trimming of Mach-Zehnder interferometers with germanium implanted arms. A phase shift of 1.2π is achieved by annealing a 7-μm implanted segment.
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11
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Multipolar passive cloaking by nonradiating anapole excitation. Sci Rep 2018; 8:12514. [PMID: 30131515 PMCID: PMC6104082 DOI: 10.1038/s41598-018-30935-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 08/03/2018] [Indexed: 11/18/2022] Open
Abstract
In this paper, we demonstrate the relation between cloaking effect and its nonradiating state by considering the destructive multipolar interaction between near-field scattering by bare object and surrounding coating located in its proximity. This cloaking effect is underpinned by anapole mode excitation and it occurs as destructive interference between the electric dipole moment, generated by a bare object (here a central metallic scatterer) and the toroidal moment, formed inside the cloak (a surrounding cluster of dielectric cylinders). Numerical results show how a cloaking effect based on the formation of the anapole mode can lead to an overall nonradiating metamolecule with all-dielectric materials in the coating region.
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