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Shu W, Qiu X, Ren Y, Zhang W, Chen L. Sorting infrared optical vortices with a nonlinear angular lens. OPTICS LETTERS 2024; 49:2918-2921. [PMID: 38824292 DOI: 10.1364/ol.522430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Accepted: 04/03/2024] [Indexed: 06/03/2024]
Abstract
Analogous to the regular lens, which spatially maps plane waves in the space domain to distinct points in the Fourier domain, the angular lens establishes the mapping relations between an angular mode and angular position, thus providing an effective toolkit for detecting an optical vortex. However, using the angular lens to sort infrared optical vortex modes via nonlinear optical processes remains relatively unexplored. Here, we design a nonlinear optical version of the angular lens to map the various infrared optical vortex modes to different angular positions in the visible region. We successfully sort nine infrared optical vortex modes of different topological charges with a visible camera, showing the cost-effective ability to sort infrared vortices compared to a relatively expensive infrared camera. Our scheme holds promise for infrared remote sensing, infrared vortex-encoded optical communications, and so on.
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2
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Shiri A, Qi R, Gbur G. Circularly coherent vortex beams optimized for propagation through turbulence. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2024; 41:B127-B134. [PMID: 38856429 DOI: 10.1364/josaa.521531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 04/23/2024] [Indexed: 06/11/2024]
Abstract
Self-focusing partially coherent beams with circular coherence have shown high potential for robust propagation through atmospheric turbulence. In this paper, we introduce a criterion to approximate the degrading effects of turbulence and we show how the coherence of the source can be optimized to generate a beam with the highest stability in turbulence. To test our prediction, we analytically compare the turbulence propagation of the OAM spectrum of circularly coherent Gaussian vortex sources with three different coherence parameters. It is shown that by satisfying the introduced optimizing conditions, we can minimize the adverse effects of turbulence on the OAM spectrum.
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3
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Gomez Sanchez O, Peng GH, Li WH, Shih CH, Chien CH, Cheng SJ. Enhanced Photo-excitation and Angular-Momentum Imprint of Gray Excitons in WSe 2 Monolayers by Spin-Orbit-Coupled Vector Vortex Beams. ACS NANO 2024; 18:11425-11437. [PMID: 38637308 PMCID: PMC11064230 DOI: 10.1021/acsnano.4c01881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 03/22/2024] [Accepted: 04/02/2024] [Indexed: 04/20/2024]
Abstract
A light beam can be spatially structured in the complex amplitude to possess orbital angular momentum (OAM), which introduces an extra degree of freedom alongside the intrinsic spin angular momentum (SAM) associated with circular polarization. Furthermore, superimposing two such twisted light (TL) beams with distinct SAM and OAM produces a vector vortex beam (VVB) in nonseparable states where not only complex amplitude but also polarization is spatially structured and entangled with each other. In addition to the nonseparability, the SAM and OAM in a VVB are intrinsically coupled by the optical spin-orbit interaction and constitute the profound spin-orbit physics in photonics. In this work, we present a comprehensive theoretical investigation, implemented on the first-principles base, of the intriguing light-matter interaction between VVBs and WSe2 monolayers (WSe2-MLs), one of the best-known and promising two-dimensional (2D) materials in optoelectronics dictated by excitons, encompassing bright exciton (BX) as well as various dark excitons (DXs). One of the key findings of our study is that a substantial enhancement of the photoexcitation of gray excitons (GXs), a type of spin-forbidden DX, in a WSe2-ML can be achieved through the utilization of a 3D-structured TL with the optical spin-orbit interaction. Moreover, we show that a spin-orbit-coupled VVB surprisingly allows for the imprinting of the carried optical information onto GXs in 2D materials, which is robust against the decoherence mechanisms in the materials. This suggests a promising method for deciphering the transferred angular momentum from structured light to excitons.
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Affiliation(s)
| | - Guan-Hao Peng
- Department
of Electrophysics, National Yang Ming Chiao
Tung University, Hsinchu 300, Taiwan
| | - Wei-Hua Li
- Department
of Electrophysics, National Yang Ming Chiao
Tung University, Hsinchu 300, Taiwan
| | - Ching-Hung Shih
- Institute
of Electronics, National Yang Ming Chiao
Tung University, Hsinchu 300, Taiwan
| | - Chao-Hsin Chien
- Institute
of Electronics, National Yang Ming Chiao
Tung University, Hsinchu 300, Taiwan
| | - Shun-Jen Cheng
- Department
of Electrophysics, National Yang Ming Chiao
Tung University, Hsinchu 300, Taiwan
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4
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Jia Y, Zhang S, Zhang X, Long H, Xu C, Bai Y, Cheng Y, Wu D, Deng M, Qiu CW, Liu X. Compact meta-differentiator for achieving isotropically high-contrast ultrasonic imaging. Nat Commun 2024; 15:2934. [PMID: 38575561 PMCID: PMC10995138 DOI: 10.1038/s41467-024-47303-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 03/25/2024] [Indexed: 04/06/2024] Open
Abstract
Ultrasonic imaging is crucial in the fields of biomedical engineering for its deep penetration capabilities and non-ionizing nature. However, traditional techniques heavily rely on impedance differences within objects, resulting in poor contrast when imaging acoustically transparent targets. Here, we propose a compact spatial differentiator for underwater isotropic edge-enhanced imaging, which enhances the imaging contrast without the need for contrast agents or external physical fields. This design incorporates an amplitude meta-grating for linear transmission along the radial direction, combined with a phase meta-grating that utilizes focus and spiral phases with a first-order topological charge. Through theoretical analysis, numerical simulations, and experimental validation, we substantiate the effectiveness of our technique in distinguishing amplitude objects with isotropic edge enhancements. Importantly, this method also enables the accurate detection of both phase objects and artificial biological models. This breakthrough creates new opportunities for applications in medical diagnosis and nondestructive testing.
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Affiliation(s)
- Yurou Jia
- Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Suying Zhang
- Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Xuan Zhang
- Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Houyou Long
- Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
| | - Caibin Xu
- College of Aerospace Engineering, Chongqing University, Chongqing, 400044, China
| | - Yechao Bai
- School of Electronic Science and Engineering, Nanjing University, Nanjing, 210023, China
| | - Ying Cheng
- Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
- State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing, 100190, China.
| | - Dajian Wu
- Jiangsu Key Lab on Opto-Electronic Technology, School of Physics and Technology, Nanjing Normal University, Nanjing, 210023, China
| | - Mingxi Deng
- College of Aerospace Engineering, Chongqing University, Chongqing, 400044, China
| | - Cheng-Wei Qiu
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Xiaojun Liu
- Department of Physics, MOE Key Laboratory of Modern Acoustics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
- State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing, 100190, China.
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5
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Zhang Y, Zhao W, Xu T, Ren Y, Zhang R, Pan Z, Yue Y. Topological charge identification of superimposed orbital angular momentum beams under turbulence using an attention mechanism. OPTICS EXPRESS 2024; 32:1941-1955. [PMID: 38297735 DOI: 10.1364/oe.507763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 12/17/2023] [Indexed: 02/02/2024]
Abstract
Due to the unique features, orbital angular momentum (OAM) beams have been widely explored for different applications. Accurate determination of the topological charge (TC) of these beams is crucial for their optimal utilization. In this paper, we propose a method that combines adaptive image processing techniques with a simple, parameter-free attention module (SimAM) based convolutional neural network to accurately identify the TC of high-order superimposed OAM beams. Experimental results demonstrate that under the combined influence of non-extreme light intensity and turbulence, it can achieve >95% identification accuracy of TCs ranging from ±1 to ±40. Moreover, even under partial-pattern-missing conditions, our method maintains an accuracy rate of over 80%. Compared with traditional attention mechanisms, SimAM does not require additional network design, significantly reducing the computational costs. Our approach showcases remarkable efficiency, robustness, and cost-effectiveness, making it adaptable to challenging factors such as non-uniform lighting and partially occluded light paths. This research provides a new direction for recognizing OAM modes with valuable implications for the future of communication systems.
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6
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Lee DH, Lee S, Bae JY, Hur H, Hyun S, Lee KS, Chang KS, Pak S, Kim DU, Jong Kim I. Spiral-phase-objective for a compact spiral-phase-contrast microscopy. OPTICS EXPRESS 2023; 31:34391-34403. [PMID: 37859196 DOI: 10.1364/oe.499376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 09/17/2023] [Indexed: 10/21/2023]
Abstract
Spiral-phase-contrast imaging, which utilizes a spiral phase optical element, has proven to be effective in enhancing various aspects of imaging, such as edge contrast and shadow imaging. Typically, the implementation of spiral-phase-contrast imaging requires the formation of a Fourier plane through a 4f optical configuration in addition to an existing optical microscope. In this study, we present what we believe to be a novel single spiral-phase-objective, integrating a spiral phase plate, which can be easily and simply applied to a standard microscope, such as a conventional objective. Using a new hybrid design approach that combines ray-tracing and field-tracing simulations, we theoretically realized a well-defined and high-quality vortex beam through the spiral-phase-objective. The spiral-phase-objective was designed to have conditions that are practically manufacturable while providing predictable performance. To evaluate its capabilities, we utilized the designed spiral-phase-objective to investigate isotropic spiral phase contrast and anisotropic shadow imaging through field-tracing simulations, and explored the variation of edge contrast caused by changes in the thickness of the imaging object.
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7
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Abstract
Metalenses have the potential to revolutionize optical devices into the next generation of consumer devices. Through new inventive strategies, metalenses with advanced functionalities have been released to integrate multiple responses into a single flat device. Here, we design metalenses that are sensitive to the incident spin angular momentum to provide three distinct modes based on the handedness of the incident and transmitted light. Propagation phase is employed to encode a hyperbolic lens phase to the metalens, while geometric phase is exploited for additional spin-selective properties. We experimentally demonstrate two different metalenses: the co-polarized channels function as a standard metalens, while the cross-polarized channels (1) deflect and (2) introduce orbital angular momentum to the transmitted light. We experimentally characterize the metalenses and prove their use for spin-selective imaging of visible light. We envision that such trichannel metalenses could be employed in chiral bioimaging, optical computing, and computer vision.
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Affiliation(s)
- Trevon Badloe
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
- Graduate School of Artificial Intelligence, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Junhwa Seong
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Junsuk Rho
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
- POSCO-POSTECH-RIST Convergence Research Center for Flat Optics and Metaphotonics, Pohang 37673, Republic of Korea
- National Institute of Nanomaterials Technology (NINT), Pohang 37673, Republic of Korea
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8
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Pushin DA, Cory DG, Kapahi C, Kulmaganbetov M, Mungalsingh M, Silva AE, Singh T, Thompson B, Sarenac D. Structured light enhanced entoptic stimuli for vision science applications. Front Neurosci 2023; 17:1232532. [PMID: 37559704 PMCID: PMC10407105 DOI: 10.3389/fnins.2023.1232532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 07/11/2023] [Indexed: 08/11/2023] Open
Abstract
The dichroic macular pigment in the Henle fiber layer in the fovea enables humans to perceive entoptic phenomena when viewing polarized blue light. In the standard case of linearly polarized stimuli, a faint bowtie-like pattern known as the Haidinger's brush appears in the central point of fixation. As the shape and clarity of the perceived signal is directly related to the health of the macula, Haidinger's brush has been used as a diagnostic marker in studies of early stage macular degeneration and central field visual dysfunction. However, due to the weak nature of the perceived signal the perception of the Haidinger's brush has not been integrated with modern clinical methods. Recent attempts have been made to increase the strength of the perceived signal by employing structured light with spatially varying polarization profiles. Here we review the advancements with the structured light stimuli and describe the current challenges and future prospects.
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Affiliation(s)
- Dmitry A. Pushin
- Department of Physics, University of Waterloo, Waterloo, ON, Canada
- Centre for Eye and Vision Research, Hong Kong, Hong Kong SAR, China
- Institute for Quantum Computing, University of Waterloo, Waterloo, ON, Canada
| | - David G. Cory
- Institute for Quantum Computing, University of Waterloo, Waterloo, ON, Canada
- Department of Chemistry, University of Waterloo, Waterloo, ON, Canada
| | - Connor Kapahi
- Department of Physics, University of Waterloo, Waterloo, ON, Canada
- Institute for Quantum Computing, University of Waterloo, Waterloo, ON, Canada
| | | | - Melanie Mungalsingh
- School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
| | - Andrew E. Silva
- School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
| | - Taranjit Singh
- Centre for Eye and Vision Research, Hong Kong, Hong Kong SAR, China
| | - Benjamin Thompson
- Centre for Eye and Vision Research, Hong Kong, Hong Kong SAR, China
- School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
| | - Dusan Sarenac
- Centre for Eye and Vision Research, Hong Kong, Hong Kong SAR, China
- Institute for Quantum Computing, University of Waterloo, Waterloo, ON, Canada
- Department of Physics, University at Buffalo, State University of New York, Buffalo, NY, United States
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9
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Badloe T, Kim Y, Kim J, Park H, Barulin A, Diep YN, Cho H, Kim WS, Kim YK, Kim I, Rho J. Bright-Field and Edge-Enhanced Imaging Using an Electrically Tunable Dual-Mode Metalens. ACS NANO 2023. [PMID: 37490514 DOI: 10.1021/acsnano.3c02471] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/27/2023]
Abstract
The imaging of microscopic biological samples faces numerous difficulties due to their small feature sizes and low-amplitude contrast. Metalenses have shown great promise in bioimaging as they have access to the complete complex information, which, alongside their extremely small and compact footprint and potential to integrate multiple functionalities into a single device, allow for miniaturized microscopy with exceptional features. Here, we design and experimentally realize a dual-mode metalens integrated with a liquid crystal cell that can be electrically switched between bright-field and edge-enhanced imaging on the millisecond scale. We combine the concepts of geometric and propagation phase to design the dual-mode metalens and physically encode the required phase profiles using hydrogenated amorphous silicon for operation at visible wavelengths. The two distinct metalens phase profiles include (1) a conventional hyperbolic metalens for bright-field imaging and (2) a spiral metalens with a topological charge of +1 for edge-enhanced imaging. We demonstrate the focusing and vortex generation ability of the metalens under different states of circular polarization and prove its use for biological imaging. This work proves a method for in vivo observation and monitoring of the cell response and drug screening within a compact form factor.
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Affiliation(s)
- Trevon Badloe
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
- Graduate School of Artificial Intelligence, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Yeseul Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Joohoon Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Hyemi Park
- Department of Biophysics, Institute of Quantum Biophysics, Sungkyunkwan University, Suwon 16419, Republic of Korea
- Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Aleksandr Barulin
- Department of Biophysics, Institute of Quantum Biophysics, Sungkyunkwan University, Suwon 16419, Republic of Korea
- Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Yen N Diep
- Department of Biophysics, Institute of Quantum Biophysics, Sungkyunkwan University, Suwon 16419, Republic of Korea
- Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Hansang Cho
- Department of Biophysics, Institute of Quantum Biophysics, Sungkyunkwan University, Suwon 16419, Republic of Korea
- Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Won-Sik Kim
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Young-Ki Kim
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Inki Kim
- Department of Biophysics, Institute of Quantum Biophysics, Sungkyunkwan University, Suwon 16419, Republic of Korea
- Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Junsuk Rho
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
- Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
- POSCO-POSTECH-RIST Convergence Research Center for Flat Optics and Metaphotonics, Pohang 37673, Republic of Korea
- National Institute of Nanomaterials Technology (NINT), Pohang 37673, Republic of Korea
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10
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B H S, Asokan S, Ivan JS. Estimation of dislocated phases and tunable orbital angular momentum using two cylindrical lenses. APPLIED OPTICS 2023; 62:3083-3092. [PMID: 37133154 DOI: 10.1364/ao.486870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
A first-order optical system consisting of two cylindrical lenses separated by a distance is considered. It is found to be non-conserving of orbital angular momentum of the incoming paraxial light field. The first-order optical system is effectively demonstrated to estimate phases with dislocations using a Gerchberg-Saxton-type phase retrieval algorithm by making use of measured intensities. Tunable orbital angular momentum in the outgoing light field is experimentally demonstrated using the considered first-order optical system by varying the distance of separation between the two cylindrical lenses.
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11
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Zhang Y, Lin P, Huo P, Liu M, Ren Y, Zhang S, Zhou Q, Wang Y, Lu YQ, Xu T. Dielectric Metasurface for Synchronously Spiral Phase Contrast and Bright-Field Imaging. NANO LETTERS 2023; 23:2991-2997. [PMID: 36971648 DOI: 10.1021/acs.nanolett.3c00388] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Spiral phase contrast imaging and bright-field imaging are two widely used modes in microscopy, providing distinct morphological information about objects. However, conventional microscopes are always unable to operate with these two modes at the same time and need additional optical elements to switch between them. Here, we present a microscopy setup that incorporates a dielectric metasurface capable of achieving spiral phase contrast imaging and bright-field imaging synchronously. The metasurface not only can focus the light for diffraction-limited imaging but also can perform a two-dimensional spatial differentiation operation by imparting an orbital angular momentum to the incident light field. This allows two spatially separated images to be simultaneously obtained, one containing high-frequency edge information and the other showing the entirety of the object. Combined with the advantages of planar architecture and ultrathin thickness of the metasurface, this approach is expected to provide support in the fields of microscopy, biomedicine, and materials science.
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Affiliation(s)
- Yanzeng Zhang
- National Laboratory of Solid-State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China
| | - Peicheng Lin
- National Laboratory of Solid-State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China
| | - Pengcheng Huo
- National Laboratory of Solid-State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, People's Republic of China
| | - Mingze Liu
- National Laboratory of Solid-State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China
| | - Yongze Ren
- National Laboratory of Solid-State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China
| | - Song Zhang
- National Laboratory of Solid-State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China
| | - Qianwei Zhou
- National Laboratory of Solid-State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China
| | - Yilin Wang
- National Laboratory of Solid-State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China
| | - Yan-Qing Lu
- National Laboratory of Solid-State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, People's Republic of China
| | - Ting Xu
- National Laboratory of Solid-State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, People's Republic of China
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12
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Munjal P, Chaudhary K, Singh KP. Noise self-canceling picoscale twisted interferometer. OPTICS LETTERS 2022; 47:5993-5996. [PMID: 37219155 DOI: 10.1364/ol.474523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 10/19/2022] [Indexed: 05/24/2023]
Abstract
We show a noise self-canceling real-time picometer scale interferometer by exploiting the unique spiral phase structure of twisted light. We use a single cylindrical interference-lens to implement the twisted interferometer and perform simultaneous measurement on N phase-orthogonal single-pixel intensity pairs chosen on the petal of the daisy-flower-like interference pattern. A cancellation of various noises by three orders of magnitude was achieved in our setup compared with a conventional single-pixel detection, enabling a sub-100 picometer resolution in measuring a non-repetitive intracavity dynamic event in real-time. Furthermore, the noise cancellation capability of the twisted interferometer scales up statistically for higher radial and azimuthal quantum numbers of the twisted light. The proposed scheme could find applications in precision metrology and in developing analogous ideas for twisted acoustic beam, electron beams, and matter waves.
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13
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Lee DH, Lee S, Yeo WJ, Jeong SK, Jeon M, Choi HJ, Kim HS, Bae JY, Kim DU, Hur H, Hyun S, Lee KS, Chang KS, Lee W, Pak S, Kim GH, Kim IJ. Wavelength-tunable spiral-phase-contrast imaging. OPTICS EXPRESS 2022; 30:27273-27284. [PMID: 36236901 DOI: 10.1364/oe.461660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 06/28/2022] [Indexed: 06/16/2023]
Abstract
Wavelength-tunable spiral-phase-contrast (SPC) imaging was experimentally accomplished in the visible wavelengths spanning a broad bandwidth of ∼200 nm based on a single off-axis spiral phase mirror (OSPM). By the rotation of an OSPM, which was designed with an integer orbital angular momentum (OAM) of l = 1 at a wavelength of 561 nm and incidence angle of 45°, high-quality SPC imaging was obtained at different wavelengths. For the comparison with wavelength-tunable SPC imaging using an OSPM, SPC imaging using a spiral phase plate (manufactured to generate an OAM of l = 1 at 561 nm) was performed at three wavelengths (473, 561, and 660 nm), resulting in clear differences. Theoretically, based on field tracing simulations, high-quality wavelength-tunable SPC imaging could be demonstrated in a very broad bandwidth of ∼400 nm, which is beyond the bandwidth of ∼200 nm obtained experimentally. This technique contribute to developing high-performance wavelength-tunable SPC imaging by simply integrating an OSPM into the current optical imaging technologies.
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14
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Fu W, Zhao D, Li Z, Liu S, Tian C, Huang K. Ultracompact meta-imagers for arbitrary all-optical convolution. LIGHT, SCIENCE & APPLICATIONS 2022; 11:62. [PMID: 35304870 PMCID: PMC8933501 DOI: 10.1038/s41377-022-00752-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 02/17/2022] [Accepted: 02/23/2022] [Indexed: 05/09/2023]
Abstract
Electronic digital convolutions could extract key features of objects for data processing and information identification in artificial intelligence, but they are time-cost and energy consumption due to the low response of electrons. Although massless photons enable high-speed and low-loss analog convolutions, two existing all-optical approaches including Fourier filtering and Green's function have either limited functionality or bulky volume, thus restricting their applications in smart systems. Here, we report all-optical convolutional computing with a metasurface-singlet or -doublet imager, considered as the third approach, where its point spread function is modified arbitrarily via a complex-amplitude meta-modulator that enables functionality-unlimited kernels. Beyond one- and two-dimensional spatial differentiation, we demonstrate real-time, parallel, and analog convolutional processing of optical and biological specimens with challenging pepper-salt denoising and edge enhancement, which significantly enrich the toolkit of all-optical computing. Such meta-imager approach bridges multi-functionality and high-integration in all-optical convolutions, meanwhile possessing good architecture compatibility with digital convolutional neural networks.
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Affiliation(s)
- Weiwei Fu
- Department of Optics and Optical Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Dong Zhao
- Department of Optics and Optical Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Ziqin Li
- Department of Optics and Optical Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Songde Liu
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, Anhui, 230088, China
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Chao Tian
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, Anhui, 230088, China.
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, Anhui, 230026, China.
| | - Kun Huang
- Department of Optics and Optical Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, China.
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15
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Ruffato G. Non-destructive OAM measurement via light-matter interaction. LIGHT, SCIENCE & APPLICATIONS 2022; 11:55. [PMID: 35273158 PMCID: PMC8913606 DOI: 10.1038/s41377-022-00749-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The detection of orbital angular momentum usually relies on optical techniques, which modify the original beam to convert the information carried on its phase into a specific intensity distribution in output. Moreover, the exploitation of high-intensity beams can result destructive for standard optical elements and setups. A recent publication suggests a solution to overcome all those limitations, by probing highly-intense vortex pulses with a structured reference beam in a strong-field photoionization process.
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Affiliation(s)
- Gianluca Ruffato
- Department of Physics and Astronomy 'G. Galilei', University of Padova, Padova, Italy.
- Quantum Technologies Research Center (QTech), University of Padova, Padova, Italy.
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16
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Fang Y, Guo Z, Ge P, Dou Y, Deng Y, Gong Q, Liu Y. Probing the orbital angular momentum of intense vortex pulses with strong-field ionization. LIGHT, SCIENCE & APPLICATIONS 2022; 11:34. [PMID: 35132069 PMCID: PMC8821541 DOI: 10.1038/s41377-022-00726-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 05/04/2023]
Abstract
With the rapid development of femtosecond lasers, the generation and application of optical vortices have been extended to the regime of intense-light-matter interaction. The characterization of the orbital angular momentum (OAM) of intense vortex pulses is very critical. Here, we propose and demonstrate a novel photoelectron-based scheme that can in situ distinguish the OAM of the focused intense femtosecond optical vortices without the modification of light helical phase. We employ two-color co-rotating intense circular fields in the strong-field photoionization experiment, in which one color light field is a plane wave serving as the probing pulses and the other one is the vortex pulses whose OAM needs to be characterized. We show that by controlling the spatial profile of the probing pulses, the OAM of the vortex pulses can be clearly identified by measuring the corresponding photoelectron momentum distributions or angle-resolved yields. This work provides a novel in situ detection scenario for the light pulse vorticity and has implications for the studies of ultrafast and intense complex light fields with optical OAM.
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Affiliation(s)
- Yiqi Fang
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Zhenning Guo
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Peipei Ge
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Yankun Dou
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Yongkai Deng
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing, 100871, China
| | - Qihuang Gong
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing, 100871, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi, 030006, China
- Center for Applied Physics and Technology, HEDPS, Peking University, Beijing, 100871, China
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China
| | - Yunquan Liu
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing, 100871, China.
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi, 030006, China.
- Center for Applied Physics and Technology, HEDPS, Peking University, Beijing, 100871, China.
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China.
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17
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Imaging through diffuse media using multi-mode vortex beams and deep learning. Sci Rep 2022; 12:1561. [PMID: 35091633 PMCID: PMC8799672 DOI: 10.1038/s41598-022-05358-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 01/11/2022] [Indexed: 01/20/2023] Open
Abstract
Optical imaging through diffuse media is a challenging issue and has attracted applications in many fields such as biomedical imaging, non-destructive testing, and computer-assisted surgery. However, light interaction with diffuse media leads to multiple scattering of the photons in the angular and spatial domain, severely degrading the image reconstruction process. In this article, a novel method to image through diffuse media using multiple modes of vortex beams and a new deep learning network named “LGDiffNet” is derived. A proof-of-concept numerical simulation is conducted using this method, and the results are experimentally verified. In this technique, the multiple modes of Gaussian and Laguerre-Gaussian beams illuminate the displayed digits dataset number, and the beams are then propagated through the diffuser before being captured on the beam profiler. Furthermore, we investigated whether imaging through diffuse media using multiple modes of vortex beams instead of Gaussian beams improves the imaging system's imaging capability and enhances the network's reconstruction ability. Our results show that illuminating the diffuser using vortex beams and employing the “LGDiffNet” network provides enhanced image reconstruction compared to existing modalities. When employing vortex beams for image reconstruction, the best NPCC is − 0.9850. However, when using Gaussian beams for imaging acquisition, the best NPCC is − 0.9837. An enhancement of 0.62 dB, in terms of PSNR, is achieved using this method when a highly scattering diffuser of grit 220 and width 2 mm (7.11 times the mean free path) is used. No additional optimizations or reference beams were used in the imaging system, revealing the robustness of the “LGDiffNet” network and the adaptability of the imaging system for practical applications in medical imaging.
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18
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Fang Y, Lu S, Liu Y. Controlling Photon Transverse Orbital Angular Momentum in High Harmonic Generation. PHYSICAL REVIEW LETTERS 2021; 127:273901. [PMID: 35061413 DOI: 10.1103/physrevlett.127.273901] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Accepted: 11/24/2021] [Indexed: 05/06/2023]
Abstract
High harmonic generation (HHG) with longitudinal optical orbital angular momentum has attracted much attention over the past decade. Here, we present the first study on the HHG with transverse orbital angular momentum driven by the spatiotemporal optical vortex (STOV) pulses. We show that the produced spatial-resolved harmonic spectra reveal unique structures, such as the spatially spectral tilt and the fine interference patterns. We show these spatiospectral structures originate from both the macroscopic and microscopic effect of spatiotemporal optical singularity in HHG. Employing two-color counterspin and countervorticity STOV pulses, we further discuss a robust method to control the spatiotemporal topological charge and spectral structure of high-order harmonics. The conservation rule of photon transverse orbital angular momentum in HHG process is also discussed when mixing with photon spin angular momenta.
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Affiliation(s)
- Yiqi Fang
- State Key Laboratory for Mesoscopic Physics and Collaborative Innovation Center of Quantum Matter, School of Physics, Peking University, Beijing 100871, China
| | - Shengyue Lu
- State Key Laboratory for Mesoscopic Physics and Collaborative Innovation Center of Quantum Matter, School of Physics, Peking University, Beijing 100871, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - Yunquan Liu
- State Key Laboratory for Mesoscopic Physics and Collaborative Innovation Center of Quantum Matter, School of Physics, Peking University, Beijing 100871, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, China
- Peking University Yangtze Delta Institute of Optoelectronics, Nantong, Jiangsu 226010, China
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19
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Kumar N, Arora A, Krishnan A. Single-shot generation of composite optical vortex beams using hybrid binary fork gratings. OPTICS EXPRESS 2021; 29:33703-33715. [PMID: 34809177 DOI: 10.1364/oe.437659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 09/05/2021] [Indexed: 06/13/2023]
Abstract
We design and experimentally demonstrate a simple, single-shot method for the generation of arbitrary composite vortex (CV) beams using hybrid binary fork gratings (hBFG). These gratings were computationally generated by removing the central region around the fork-dislocation of azimuthal charge ℓ1 and substituting it with a BFG of a different charge ℓ2. The geometrical parameters of hBFGs were optimized for the efficient generation of CV beams. The method was further extended to the generation of CV beams consisting of three different ℓ and of higher radial charges p. This simple generation method may be useful to generate complex beam shapes with engineered phase fronts without complicated interferometry based techniques.
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20
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Wang T, Lu J, Yao H, Shi F, Meng L, Cheng P, Zeng X. Recent progress in all-fiber ultrafast high-order mode lasers. JPHYS PHOTONICS 2021. [DOI: 10.1088/2515-7647/abc898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Abstract
Ultrafast high-order mode (HOM) lasers are a relatively new class of ultrafast optics. They play a significant role in the fieldsof scientific research and industrial applications due to the high peak power and unique properties of spatial intensity and polarization distribution. Generation of ultrafast HOM beams in all-fiber systems has become an important research direction. In this paper, all-fiber mode conversion techniques, pulsed HOM laser strategies, and few-mode/multi-mode fiber (FMF/MMF) lasers are reviewed. The main motivation of this review is to highlight recent advances in the field of all-fiber ultrafast HOM lasers, for example, generating different HOM pulses based on fiber mode converters and mode-locking in the FMF/MMF lasers. These results suggest that mode selective coupler can be used as a broad bandwidth mode converter with fast response and HOM can be directly oscillated in the FMF/MMF laser cavity with high stability. In addition, spatiotemporal mode-locking in the FMF/MMF is also involved. It is believed that the development of all-fiber ultrafast HOM lasers will continue to deepen, thus laying a good foundation for future applications.
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21
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Ding Y, Gudapati V, Lin R, Fei Y, Sevag Packard RR, Song S, Chang CC, Baek KI, Wang Z, Roustaei M, Kuang D, Jay Kuo CC, Hsiai TK. Saak Transform-Based Machine Learning for Light-Sheet Imaging of Cardiac Trabeculation. IEEE Trans Biomed Eng 2021; 68:225-235. [PMID: 32365015 PMCID: PMC7606319 DOI: 10.1109/tbme.2020.2991754] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
OBJECTIVE Recent advances in light-sheet fluorescence microscopy (LSFM) enable 3-dimensional (3-D) imaging of cardiac architecture and mechanics in toto. However, segmentation of the cardiac trabecular network to quantify cardiac injury remains a challenge. METHODS We hereby employed "subspace approximation with augmented kernels (Saak) transform" for accurate and efficient quantification of the light-sheet image stacks following chemotherapy-treatment. We established a machine learning framework with augmented kernels based on the Karhunen-Loeve Transform (KLT) to preserve linearity and reversibility of rectification. RESULTS The Saak transform-based machine learning enhances computational efficiency and obviates iterative optimization of cost function needed for neural networks, minimizing the number of training datasets for segmentation in our scenario. The integration of forward and inverse Saak transforms can also serve as a light-weight module to filter adversarial perturbations and reconstruct estimated images, salvaging robustness of existing classification methods. The accuracy and robustness of the Saak transform are evident following the tests of dice similarity coefficients and various adversary perturbation algorithms, respectively. The addition of edge detection further allows for quantifying the surface area to volume ratio (SVR) of the myocardium in response to chemotherapy-induced cardiac remodeling. CONCLUSION The combination of Saak transform, random forest, and edge detection augments segmentation efficiency by 20-fold as compared to manual processing. SIGNIFICANCE This new methodology establishes a robust framework for post light-sheet imaging processing, and creating a data-driven machine learning for automated quantification of cardiac ultra-structure.
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Affiliation(s)
- Yichen Ding
- Henry Samueli School of Engineering and David Geffen School of Medicine, University of California, Los Angeles, CA 90095 USA
| | - Varun Gudapati
- Henry Samueli School of Engineering and David Geffen School of Medicine, University of California, Los Angeles, CA 90095 USA
| | - Ruiyuan Lin
- Ming-Hsieh Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Yanan Fei
- Ming-Hsieh Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - René R Sevag Packard
- Henry Samueli School of Engineering and David Geffen School of Medicine, University of California, Los Angeles, CA 90095 USA
| | - Sibo Song
- Ming-Hsieh Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Chih-Chiang Chang
- Henry Samueli School of Engineering and David Geffen School of Medicine, University of California, Los Angeles, CA 90095 USA
| | - Kyung In Baek
- Henry Samueli School of Engineering and David Geffen School of Medicine, University of California, Los Angeles, CA 90095 USA
| | - Zhaoqiang Wang
- Henry Samueli School of Engineering and David Geffen School of Medicine, University of California, Los Angeles, CA 90095 USA
| | - Mehrdad Roustaei
- Henry Samueli School of Engineering and David Geffen School of Medicine, University of California, Los Angeles, CA 90095 USA
| | - Dengfeng Kuang
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, and Institute of Modern Optics, Nankai University, Tianjin 300350, China
| | - C.-C. Jay Kuo
- Ming-Hsieh Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Tzung K. Hsiai
- Henry Samueli School of Engineering and David Geffen School of Medicine, University of California, Los Angeles, CA 90095 USA
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22
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Liu SK, Li YH, Liu SL, Zhou ZY, Li Y, Yang C, Guo GC, Shi BS. Real-time quantum edge enhanced imaging. OPTICS EXPRESS 2020; 28:35415-35426. [PMID: 33379656 DOI: 10.1364/oe.395910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 10/20/2020] [Indexed: 06/12/2023]
Abstract
With the development of optical information processing technology, image edge enhancement technology has rapidly received extensive attention, especially in the field of quantum imaging. However, quantum edge enhanced imaging faces challenges in terms of time-consuming acquisition processes and the complexity of the devices used, which limits practical applications in real-time usage scenarios. Here we introduce and experimentally demonstrate a real-time (0.5 Hz) quantum edge enhanced imaging method that combines the spiral phase contrast technique with heralded single-photon imaging. The edge enhancement results show high quality and background free from raw data. Compared with direct imaging, our configuration can improve the signal-to-noise ratio significantly using the tight time correlations between photon pairs. The method also offers competitive advantages over ghost imaging, including higher brightness and a compact optical fiber delay rather than a free space delay. Additionally, we explore curved edge enhancement for specific feature recognition and the oriented shadow effect. Overall, this efficient and versatile platform paves an alternative path toward real-time quantum edge detection in applications including nondestructive bio-imaging, night vision and covert monitoring.
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23
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Rickenstorff C, Gómez-Pavón LDC, Sosa-Sánchez CT, Silva-Ortigoza G. Paraxial and tightly focused behaviour of the double ring perfect optical vortex. OPTICS EXPRESS 2020; 28:28713-28726. [PMID: 32988136 DOI: 10.1364/oe.403600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 09/01/2020] [Indexed: 06/11/2023]
Abstract
In this paper we compare the intensity distributions in the paraxial and tightly focused regimes corresponding to a double ring perfect optical vortex (DR-POV). Using the scalar diffraction theory and the Richards-Wolf formalism, the fields in the back focal plane of a low and high (tight focusing) NA lens are calculated. In the paraxial case we experimentally observed a DR-POV whose rings enclose a dark zone thanks to the destructive interference introduced by a π phase shift. In the tightly focused regime, however, the numerical simulations showed that the intensity near the focus is influenced by the input field polarization and it is not intuitive. In both cases we found that the dark region subtended between the rings has a minimal width that is inversely proportional to the pupil radius of the system, reaching 0.42λ for the radially polarized DR-POV. For the tightly focused case, we calculated the optical forces in the transversal and longitudinal coordinates exerted on a metallic particle. As a result, it is theoretically demonstrated that the circularly polarized DR-POV can trap Au metallic particles in 3D using a light wavelength close to its resonance.
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24
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Abstract
Recent technological advances have enabled the creation of custom light fields with remarkable properties. Here we report an experiment that merges human visual perception with structured wavefronts and optical states that are nonseparable in polarization and spatial modes of light. We demonstrate that humans are able to discriminate between two polarization-coupled orbital angular momentum states with a high probability when directly viewing a structured light beam. The work brings the techniques of structured light to visual science applications and paves the way for methods of characterizing the structure of the macula and conducting experiments with human detectors and optical states with nonseparable modes. We predict and experimentally verify an entoptic phenomenon through which humans are able to perceive and discriminate optical spin–orbit states. Direct perception and discrimination of these particular states of light with polarization-coupled spatial modes is possible through the observation of distinct profiles induced by the interaction between polarization topologies and the radially symmetric dichroic elements that are centered on the foveola in the macula of the human eye. A psychophysical study was conducted where optical states with a superposition of right and left circular polarization coupled to two different orbital angular momentum (OAM) values (ℓ1 and ℓ2) were directed onto the retina of participants. The number of azimuthal fringes that a human sees when viewing the spin–orbit states is shown to be equal to the number (N) of radial lines in the corresponding polarization profile of the beam, where N=|(ℓ1−ℓ2)−2|. The participants were able to correctly discriminate between two states carrying OAM =7 and differentiated by N=5 and N=9, with an average success probability of 77.6% (average sensitivity d′=1.7, t(9)=5.9, p=2×10−4). These results enable methods of robustly characterizing the structure of the macula, probing retina signaling pathways, and conducting experiments with human detectors and optical states with nonseparable modes.
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25
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Wei S, Earl SK, Lin J, Kou SS, Yuan XC. Active sorting of orbital angular momentum states of light with a cascaded tunable resonator. LIGHT, SCIENCE & APPLICATIONS 2020; 9:10. [PMID: 32025293 PMCID: PMC6987156 DOI: 10.1038/s41377-020-0243-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 12/23/2019] [Accepted: 12/25/2019] [Indexed: 05/14/2023]
Abstract
The orbital angular momentum (OAM) of light has been shown to be useful in diverse fields ranging from astronomy and optical trapping to optical communications and data storage. However, one of the primary impediments preventing such applications from widespread adoption is the lack of a straightforward and dynamic method to sort incident OAM states without altering the states. Here, we report a technique that can dynamically filter individual OAM states and preserve the incident OAM states for subsequent processing. Although the working principle of this technique is based on resonance, the device operation is not limited to a particular wavelength. OAM states with different wavelengths can resonate in the resonator without any additional modulation other than changing the length of the cavity. Consequently, we are able to demonstrate a reconfigurable OAM sorter that is constructed by cascading such optical resonators. This approach does not require specially designed components and is readily amenable to integration into potential applications.
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Affiliation(s)
- Shibiao Wei
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Shenzhen University, Shenzhen, 518060 China
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science (LIMS), La Trobe University, Victoria, 3086 Australia
- School of Engineering, RMIT University, Melbourne, Victoria, 3001 Australia
| | - Stuart K. Earl
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science (LIMS), La Trobe University, Victoria, 3086 Australia
- School of Engineering, RMIT University, Melbourne, Victoria, 3001 Australia
| | - Jiao Lin
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Shenzhen University, Shenzhen, 518060 China
- School of Engineering, RMIT University, Melbourne, Victoria, 3001 Australia
- School of Physics, The University of Melbourne, Tin Alley, Melbourne, Victoria, 3010 Australia
| | - Shan Shan Kou
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science (LIMS), La Trobe University, Victoria, 3086 Australia
| | - Xiao-Cong Yuan
- Nanophotonics Research Center, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Shenzhen University, Shenzhen, 518060 China
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26
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Ruffato G, Massari M, Romanato F. Multiplication and division of the orbital angular momentum of light with diffractive transformation optics. LIGHT, SCIENCE & APPLICATIONS 2019; 8:113. [PMID: 31814970 PMCID: PMC6892886 DOI: 10.1038/s41377-019-0222-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 11/05/2019] [Accepted: 11/11/2019] [Indexed: 05/25/2023]
Abstract
We present a method to efficiently multiply or divide the orbital angular momentum (OAM) of light beams using a sequence of two optical elements. The key element is represented by an optical transformation mapping the azimuthal phase gradient of the input OAM beam onto a circular sector. By combining multiple circular-sector transformations into a single optical element, it is possible to multiply the value of the input OAM state by splitting and mapping the phase onto complementary circular sectors. Conversely, by combining multiple inverse transformations, the division of the initial OAM value is achievable by mapping distinct complementary circular sectors of the input beam into an equal number of circular phase gradients. Optical elements have been fabricated in the form of phase-only diffractive optics with high-resolution electron-beam lithography. Optical tests confirm the capability of the multiplier optics to perform integer multiplication of the input OAM, whereas the designed dividers are demonstrated to correctly split up the input beam into a complementary set of OAM beams. These elements can find applications for the multiplicative generation of higher-order OAM modes, optical information processing based on OAM beam transmission, and optical routing/switching in telecom.
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Affiliation(s)
- Gianluca Ruffato
- Department of Physics and Astronomy ‘G. Galilei’, University of Padova, via Marzolo 8, 35131 Padova, Italy
- LaNN, Laboratory for Nanofabrication of Nanodevices, EcamRicert, Corso StatiUniti 4, 35127 Padova, Italy
| | - Michele Massari
- LaNN, Laboratory for Nanofabrication of Nanodevices, EcamRicert, Corso StatiUniti 4, 35127 Padova, Italy
- CNR-INFM TASC IOM National Laboratory, S.S. 14 Km 163.5, 34012 Trieste, Italy
| | - Filippo Romanato
- Department of Physics and Astronomy ‘G. Galilei’, University of Padova, via Marzolo 8, 35131 Padova, Italy
- LaNN, Laboratory for Nanofabrication of Nanodevices, EcamRicert, Corso StatiUniti 4, 35127 Padova, Italy
- CNR-INFM TASC IOM National Laboratory, S.S. 14 Km 163.5, 34012 Trieste, Italy
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27
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Tian Q, Xu B, Li N, Luo Z, Xu H, Cai Z. Direct generation of orthogonally polarized dual-wavelength continuous-wave and passively Q-switched vortex beam in diode-pumped Pr:YLF lasers. OPTICS LETTERS 2019; 44:5586-5589. [PMID: 31730114 DOI: 10.1364/ol.44.005586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 10/18/2019] [Indexed: 06/10/2023]
Abstract
We report on direct generation of an orthogonally polarized dual-wavelength vortex laser, for the first time to our knowledge, by means of a diode-pumped V-shaped Pr:YLF laser platform. A method of misaligning the folded mirror is proposed to realize the simultaneous orthogonally polarized dual-wavelength laser, while a method of orthogonally rotating the laser gain medium is proposed to generate an intracavity vortex beam (LG01 mode). With the two methods, in continuous-wave (CW) mode, we have achieved simultaneous lasing of an orthogonally polarized dual-wavelength vortex laser at 604 and 607 nm with maximum output power of 237.7 mW. Moreover, based on this operation, a simultaneous orthogonally polarized dual-wavelength passively Q-switched vortex laser is also realized by inserting a Co:ASL crystal into the laser resonator as a saturable absorber. This work provides the simplest way for direct generation of an orthogonally polarized dual-wavelength vortex laser for potential applications.
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28
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Ruffato G, Massari M, Girardi M, Parisi G, Zontini M, Romanato F. Non-paraxial design and fabrication of a compact OAM sorter in the telecom infrared. OPTICS EXPRESS 2019; 27:24123-24134. [PMID: 31510306 DOI: 10.1364/oe.27.024123] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 07/01/2019] [Indexed: 06/10/2023]
Abstract
A novel optical device is designed and fabricated in order to overcome the limits of the traditional sorter based on log-pol optical transformation for the demultiplexing of optical beams carrying orbital angular momentum (OAM). The proposed configuration simplifies the alignment procedure and significantly improves the compactness and miniaturization level of the optical architecture. Since the device requires to operate beyond the paraxial approximation, a rigorous formulation of transformation optics in the non-paraxial regime has been developed and applied. The sample has been fabricated as 256-level phase-only diffractive optics with high-resolution electron-beam lithography, and tested for the demultiplexing of OAM beams at the telecom wavelength of 1310 nm. The designed sorter can find promising applications in next-generation optical platforms for mode-division multiplexing based on OAM modes both for free-space and multi-mode fiber transmission.
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29
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Holographic Silicon Metasurfaces for Total Angular Momentum Demultiplexing Applications in Telecom. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9112387] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The simultaneous processing of orbital angular momentum (OAM) and polarization has recently acquired particular importance and interest in a wide range of fields ranging from telecommunications to high-dimensional quantum cryptography. Due to their inherently polarization-sensitive optical behavior, Pancharatnam–Berry optical elements (PBOEs), acting on the geometric phase, have proven to be useful for the manipulation of complex light beams with orthogonal polarization states using a single optical element. In this work, different PBOEs have been computed, realized, and optically analyzed for the sorting of beams with orthogonal OAM and polarization states at the telecom wavelength of 1310 nm. The geometric-phase control is obtained by inducing a spatially-dependent form birefringence on a silicon substrate, patterned with properly-oriented subwavelength gratings. The digital grating structure is generated with high-resolution electron beam lithography on a resist mask and transferred to the silicon substrate using inductively coupled plasma-reactive ion etching. The optical characterization of the fabricated samples confirms the expected capability to detect circularly-polarized optical vortices with different handedness and orbital angular momentum.
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30
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Lin F, Qiu X, Zhang W, Chen L. Seeing infrared optical vortex arrays with a nonlinear spiral phase filter. OPTICS LETTERS 2019; 44:2298-2301. [PMID: 31042208 DOI: 10.1364/ol.44.002298] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 03/31/2019] [Indexed: 06/09/2023]
Abstract
We demonstrate a new method to detect infrared optical vortex arrays efficiently, which is based on simultaneous up-conversion imaging and spiral phase contrast via second-harmonic generation (SHG) in the Fourier domain. In our experiment, we use a spatial light modulator to prepare a variety of 1064 nm structured vortex arrays and employ a vortex phase plate of different topological charges to serve as the nonlinear orbital angular momentum (OAM) filter. The SHG is done by mixing the Fourier spectra of input-structured vortices with a single OAM beam in a type-II potassium titanyl phosphate crystal. Then we can convert the input invisible vortex arrays into the visible SHG light fields, and the vortex cores are mapped and seen by bright Gaussian spots, revealing both their positions and topological charges. Our work has potential in the field of infrared imaging and monitoring.
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Qiu X, Zhang D, Zhang W, Chen L. Structured-Pump-Enabled Quantum Pattern Recognition. PHYSICAL REVIEW LETTERS 2019; 122:123901. [PMID: 30978085 DOI: 10.1103/physrevlett.122.123901] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Indexed: 06/09/2023]
Abstract
We report a new scheme of ghost imaging by using a spatially structured pump in the Fourier domain of spontaneous parametric down-conversion for quantum-correlation-based pattern recognition. We exploit the mathematical feature of Laguerre-Gaussian mode's Fourier transform to describe the pump-modulated formation of a ghost image. Of particular interest is the experimental demonstration of a quantum equivalence of a Vander Lugt filter, based on which the nonlocal spiral phase contrast for vortex mapping and quantum-correlation-based human face recognition are implemented successfully. The photons used for probing a test object, scanning the database, and producing a correlation signal can belong to three different light beams, which suggests some security applications where low-light-level illumination and covert operation are desired.
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Affiliation(s)
- Xiaodong Qiu
- Department of Physics, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, and Jiujiang Research Institute, Xiamen University, Xiamen 361005, China
| | - Dongkai Zhang
- Department of Physics, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, and Jiujiang Research Institute, Xiamen University, Xiamen 361005, China
| | - Wuhong Zhang
- Department of Physics, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, and Jiujiang Research Institute, Xiamen University, Xiamen 361005, China
| | - Lixiang Chen
- Department of Physics, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, and Jiujiang Research Institute, Xiamen University, Xiamen 361005, China
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32
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Brasselet E. Tunable High-Resolution Macroscopic Self-Engineered Geometric Phase Optical Elements. PHYSICAL REVIEW LETTERS 2018; 121:033901. [PMID: 30085767 DOI: 10.1103/physrevlett.121.033901] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Indexed: 05/09/2023]
Abstract
Artificially engineered geometric phase optical elements may have tunable photonic functionalities owing to their sensitivity to external fields, as is the case for liquid crystal based devices. However, liquid crystal technology combining high-resolution topological ordering with tunable spectral behavior remains elusive. Here, by using a magnetoelectric external stimulus, we create robust and efficient self-engineered liquid crystal geometric phase vortex masks with a broadly tunable operating wavelength, centimeter-size clear aperture, and high-quality topological ordering.
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Szedlak R, Hisch T, Schwarz B, Holzbauer M, MacFarland D, Zederbauer T, Detz H, Andrews AM, Schrenk W, Rotter S, Strasser G. Ring quantum cascade lasers with twisted wavefronts. Sci Rep 2018; 8:7998. [PMID: 29789653 PMCID: PMC5964118 DOI: 10.1038/s41598-018-26267-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 05/09/2018] [Indexed: 11/15/2022] Open
Abstract
We demonstrate the on-chip generation of twisted light beams from ring quantum cascade lasers. A monolithic gradient index metamaterial is fabricated directly into the substrate side of the semiconductor chip and induces a twist of the light's wavefront. This significantly influences the obtained beam pattern, which changes from a central intensity minimum to a maximum depending on the discontinuity count of the metamaterial. Our design principle provides an interesting alternative to recent implementations of microlasers operating at an exceptional point.
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Affiliation(s)
- Rolf Szedlak
- Institute of Solid State Electronics & Center for Micro- and Nanostructures, TU Wien, Floragasse 7, 1040, Vienna, Austria.
| | - Thomas Hisch
- Institute for Theoretical Physics, TU Wien, Wiedner-Hauptstraße 8-10/136, 1040, Vienna, Austria
| | - Benedikt Schwarz
- Institute of Solid State Electronics & Center for Micro- and Nanostructures, TU Wien, Floragasse 7, 1040, Vienna, Austria
| | - Martin Holzbauer
- Institute of Solid State Electronics & Center for Micro- and Nanostructures, TU Wien, Floragasse 7, 1040, Vienna, Austria
| | - Donald MacFarland
- Institute of Solid State Electronics & Center for Micro- and Nanostructures, TU Wien, Floragasse 7, 1040, Vienna, Austria
| | - Tobias Zederbauer
- Institute of Solid State Electronics & Center for Micro- and Nanostructures, TU Wien, Floragasse 7, 1040, Vienna, Austria
| | - Hermann Detz
- Austrian Academy of Sciences, Dr. Ignaz Seipel-Platz 2, 1010, Vienna, Austria
| | - Aaron Maxwell Andrews
- Institute of Solid State Electronics & Center for Micro- and Nanostructures, TU Wien, Floragasse 7, 1040, Vienna, Austria
| | - Werner Schrenk
- Institute of Solid State Electronics & Center for Micro- and Nanostructures, TU Wien, Floragasse 7, 1040, Vienna, Austria
| | - Stefan Rotter
- Institute for Theoretical Physics, TU Wien, Wiedner-Hauptstraße 8-10/136, 1040, Vienna, Austria
| | - Gottfried Strasser
- Institute of Solid State Electronics & Center for Micro- and Nanostructures, TU Wien, Floragasse 7, 1040, Vienna, Austria
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Gozali R, Nguyen TA, Bendau E, Alfano RR. Compact OAM microscope for edge enhancement of biomedical and object samples. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:093701. [PMID: 28964247 DOI: 10.1063/1.5000508] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 08/15/2017] [Indexed: 06/07/2023]
Abstract
The production of orbital angular momentum (OAM) by using a q-plate, which functions as an electrically tunable spatial frequency filter, provides a simple and efficient method of edge contrast in biological and medical sample imaging for histological evaluation of tissue, smears, and PAP smears. An instrument producing OAM, such as a q-plate, situated at the Fourier plane of a 4f lens system, similar to the use of a high-pass spatial filter, allows the passage of high spatial frequencies and enables the production of an image with highly illuminated edges contrasted against a dark background for both opaque and transparent objects. Compared with ordinary spiral phase plates and spatial light modulators, the q-plate has the added advantage of electric control and tunability.
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Affiliation(s)
- Richard Gozali
- Department of Physics, Institute for Ultrafast Spectroscopy and Lasers, Complex Light Center, City College of New York, 160 Convent Avenue, New York, New York 10031, USA
| | - Thien-An Nguyen
- Department of Physics, Institute for Ultrafast Spectroscopy and Lasers, Complex Light Center, City College of New York, 160 Convent Avenue, New York, New York 10031, USA
| | - Ethan Bendau
- Department of Physics, Institute for Ultrafast Spectroscopy and Lasers, Complex Light Center, City College of New York, 160 Convent Avenue, New York, New York 10031, USA
| | - Robert R Alfano
- Department of Physics, Institute for Ultrafast Spectroscopy and Lasers, Complex Light Center, City College of New York, 160 Convent Avenue, New York, New York 10031, USA
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Mitin N, Pikulin A. Generation of photonic vortex lattices with colloidal monolayers of dielectric microparticles. OPTICS LETTERS 2017; 42:2527-2530. [PMID: 28957276 DOI: 10.1364/ol.42.002527] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 06/02/2017] [Indexed: 06/07/2023]
Abstract
It is shown that colloidal monolayers of dielectric microparticles with high refractive index (e.g., titania, zirconia) can convert incident, circularly polarized laser light into the lattice of photonic vortices that carry orbital angular momentum. Such particle monolayers are formed via self-assembly on various surfaces. Properties of the vortices are studied analytically, taking into account the symmetry of the problem. Vortex lattices of topological charges m=+-1 and two different polarizations are shown to be possible. Generation of the vortex lattices by the spherical and spheroidal particles irradiated by femtosecond laser pulses is studied using the finite difference time domain simulation. The vortex generation efficiency depending on the particle parameters is analyzed.
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Barnett SM, Babiker M, Padgett MJ. Optical orbital angular momentum. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2017; 375:rsta.2015.0444. [PMID: 28069775 PMCID: PMC5247487 DOI: 10.1098/rsta.2015.0444] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/19/2016] [Indexed: 05/09/2023]
Abstract
We present a brief introduction to the orbital angular momentum of light, the subject of our theme issue and, in particular, to the developments in the 13 years following the founding paper by Allen et al. (Allen et al. 1992 Phys. Rev. A 45, 8185 (doi:10.1103/PhysRevA.45.8185)). The papers by our invited authors serve to bring the field up to date and suggest where developments may take us next.This article is part of the themed issue 'Optical orbital angular momentum'.
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Affiliation(s)
- Stephen M Barnett
- School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK
| | - Mohamed Babiker
- Department of Physics, University of York, Heslington, York YO10 5DD, UK
| | - Miles J Padgett
- School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK
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