1
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Hu H, Li H, Qin X, Li X. Where is the orbital angular momentum in vortex superposition states? OPTICS EXPRESS 2024; 32:16156-16163. [PMID: 38859251 DOI: 10.1364/oe.523305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Accepted: 03/29/2024] [Indexed: 06/12/2024]
Abstract
In this paper, we explore the distribution of the orbital angular momentum (OAM) in the coaxial vortex superposition states based on the independent propagation principle of light in this interference process. We find that in this case, some specific singular points exist in the spatial intensity distribution. The first type of singular point is located at the center point of the spatial intensity distribution. The second type of specific singular point is at the critical location of the overlapping area in angular direction. By analogy with the angular momentum superposition of two axially rotating homogeneous disks with different radius in rigid body, We present a suggestion: the center point is located at the overlapping area of all the superposed components. Therefore, the topological charge value in the center point should be doubled by the actual number of superposition field components. The singular point at the critical location of the overlapping area in angular direction should also be co-owned by the superposition components outside the position of the ring (including the corresponding component of the ring). The total OAM is exactly equal to the sum of those two types contained in the superposition states, which is equal to the input OAM of the superposition state components. The conservation of the OAM in the coaxial interference process is demonstrated.
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2
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Shi Y, Wan S, Dai C, Wang Z, Li Z, Li Z. On-Chip Meta-Optics for Engineering Arbitrary Trajectories with Longitudinal Polarization Variation. NANO LETTERS 2024; 24:2063-2070. [PMID: 38299886 DOI: 10.1021/acs.nanolett.3c04739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
Abstract
On-chip integrated meta-optics promise to achieve high-performance and compact integrated photonic devices. To arbitrarily engineer the optical trajectory along the propagation path in an on-chip integrated scheme is of significance in fundamental physics and various emerging applications. Here, we experimentally demonstrate an on-chip metasurface integrated on a waveguide to enable predefined arbitrary optical trajectories in the visible regime. By transformation of the transverse phase to generate longitudinal mapping, the guided waves are extracted and molded into any different optical trajectories (parabola, hyperbola, and cosine). More intriguingly, predefined polarization states with longitudinal variation are also successfully imparted along the trajectory. Owing to the on-chip propagation scheme, the trajectories are uniquely free from zero-order diffraction interference, naturally having a higher signal-to-noise ratio beyond conventional free-space forms. Overall, such on-chip optical trajectory engineering allows for miniaturized integration and can find paths in potential applications of complex optical manipulation, advanced laser fabrication, and microscopic imaging.
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Affiliation(s)
- Yangyang Shi
- Electronic Information School, Wuhan University, Wuhan 430072, China
| | - Shuai Wan
- Electronic Information School, Wuhan University, Wuhan 430072, China
| | - Chenjie Dai
- Electronic Information School, Wuhan University, Wuhan 430072, China
| | - Zejing Wang
- Electronic Information School, Wuhan University, Wuhan 430072, China
| | - Zhe Li
- Electronic Information School, Wuhan University, Wuhan 430072, China
| | - Zhongyang Li
- Electronic Information School, Wuhan University, Wuhan 430072, China
- Wuhan Institute of Quantum Technology, Wuhan 430206, China
- School of Microelectronics, Wuhan University, Wuhan 430072, China
- Suzhou Institute of Wuhan University, Suzhou 215123, China
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3
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Qu MJ, Tian RW, Li WY, Su JX. Spatial Bessel-like beams along arbitrary convex trajectories based on a 3D-printed metasurface. OPTICS LETTERS 2022; 47:3507-3510. [PMID: 35838714 DOI: 10.1364/ol.465481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 06/19/2022] [Indexed: 06/15/2023]
Abstract
A 3D-printed all-dielectric metasurface is presented in this Letter which can generate an accelerating beam with a circularly symmetric non-spreading transverse profile that can propagate along arbitrary convex trajectories. The curved trajectory is mapped to the corresponding direct-space spatial phases by the basic cube units with different geometrical heights. The required phase distribution is derived in detail based on the enveloping theory of differential geometry and the Bessel beam generation method. A metasurface with a preset trajectory is simulated and measured to demonstrate the validity of the phase distribution calculated by the proposed theory. The full-wave simulation and measurement results verify that the Bessel-like beam whose intensity follows a curved (off-axis) trajectory can be produced by the proposed metasurface. The generated hybrid beam merges the advantages of non-accelerating and accelerating diffractive-free beams. Therefore, the proposed metasurface has great potential in ultrahigh-speed communication, secure communication, near-field imaging, wireless energy transmission applications, and so on. The all-dielectric characteristic provides the proposed metasurface with the competitive advantages of low cost and easy large-scale processing.
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4
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Singh AV, Pertsch T. Spatio-temporal propagation dynamics of Airy plasmon pulses. OPTICS EXPRESS 2022; 30:484-495. [PMID: 35201224 DOI: 10.1364/oe.439764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Accepted: 11/10/2021] [Indexed: 06/14/2023]
Abstract
We investigate numerically the evolution of a particular type of non-diffracting pulsed plasmonic beam called Airy plasmon pulses. A suitable diffraction grating is obtained by optimizing a grating (e.g., [Phys. Rev. Lett.107, 116802 (2011)10.1103/PhysRevLett.107.116802]) for maximum generation bandwidth and efficiency to excite ultrashort Airy plasmon pulses. The optimization process is based on Airy and non-Airy plasmons contributions from the diffraction grating. The time-averaged Airy plasmon pulse generated from the grating shows a bent trajectory and quasi non-diffracting properties similar to CW excited Airy plasmons. A design-parameter-dependent geometrical model is developed to explain the spatio-temporal dynamics of the Airy plasmon pulses, which predicts the pulse broadening in Airy plasmon pulses due to non-Airy plasmons emerging from the grating. This model provides a parametric design control for the potential engineering of temporally focused 2D non-diffracting pulsed plasmonic beams.
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5
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Wan L, Pan D, Feng T, Liu W, Potapov AA. A review of dielectric optical metasurfaces for spatial differentiation and edge detection. FRONTIERS OF OPTOELECTRONICS 2021; 14:187-200. [PMID: 36637663 PMCID: PMC9743909 DOI: 10.1007/s12200-021-1124-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 12/28/2020] [Indexed: 05/05/2023]
Abstract
Dielectric metasurfaces-based planar optical spatial differentiator and edge detection have recently been proposed to play an important role in the parallel and fast image processing technology. With the development of dielectric metasurfaces of different geometries and resonance mechanisms, diverse on-chip spatial differentiators have been proposed by tailoring the dispersion characteristics of subwavelength structures. This review focuses on the basic principles and characteristic parameters of dielectric metasurfaces as first- and second-order spatial differentiators realized via the Green's function approach. The spatial bandwidth and polarization dependence are emphasized as key properties by comparing the optical transfer functions of metasurfaces for different incident wavevectors and polarizations. To present the operational capabilities of a two-dimensional spatial differentiator in image information acquisition, edge detection is described to illustrate the practicability of the device. As an application example, experimental demonstrations of edge detection for different biological cells and a flower mold are discussed, in which a spatial differentiator and objective lens or camera are integrated in three optical pathway configurations. The realization of spatial differentiators and edge detection with dielectric metasurfaces provides new opportunities for ultrafast information identification in biological imaging and machine vision.
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Affiliation(s)
- Lei Wan
- Department of Electronic Engineering, College of Information Science and Technology, Jinan University, Guangzhou, 510632, China.
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China.
- JNU-IREE RAS Joint Laboratory of Information Techniques and Fractal Signal Processing, Jinan University, Guangzhou, 510632, China.
- Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Education Institutes, Jinan University, Guangzhou, 510632, China.
| | - Danping Pan
- Department of Electronic Engineering, College of Information Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Tianhua Feng
- Department of Electronic Engineering, College of Information Science and Technology, Jinan University, Guangzhou, 510632, China.
- JNU-IREE RAS Joint Laboratory of Information Techniques and Fractal Signal Processing, Jinan University, Guangzhou, 510632, China.
| | - Weiping Liu
- Department of Electronic Engineering, College of Information Science and Technology, Jinan University, Guangzhou, 510632, China
- Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Education Institutes, Jinan University, Guangzhou, 510632, China
| | - Alexander A Potapov
- JNU-IREE RAS Joint Laboratory of Information Techniques and Fractal Signal Processing, Jinan University, Guangzhou, 510632, China
- Institute of Radio Engineering and Electronics, Russian Academy of Sciences, Moscow, 125009, Russia
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6
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Talukdar TH, Ryckman JD. Multifunctional focusing and accelerating of light with a simple flat lens. OPTICS EXPRESS 2020; 28:30597-30605. [PMID: 33115057 DOI: 10.1364/oe.402572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 09/23/2020] [Indexed: 06/11/2023]
Abstract
The wavefronts emerging from phase gradient metasurfaces are typically sensitive to incident beam properties such as angle, wavelength, or polarization. While this sensitivity can result in undesired wavefront aberrations, it can also be exploited to construct multifunctional devices which dynamically vary their behavior in response to tuning a specified degree of freedom. Here, we show how incident beam tilt in a one dimensional metalens naturally offers a means for changing functionality between diffraction limited focusing and the generation of non-paraxial accelerating light beams. This attractively offers enhanced control over accelerating beam characteristics in a simple and compact form factor.
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7
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Aborahama Y, Dorrah AH, Mojahedi M. Designing the phase and amplitude of scalar optical fields in three dimensions. OPTICS EXPRESS 2020; 28:24721-24730. [PMID: 32907006 DOI: 10.1364/oe.397119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 07/22/2020] [Indexed: 06/11/2023]
Abstract
The ability to generate any arbitrarily chosen optical field in a three-dimensional (3D) space, in the absence of any sources, without modifying the index of refraction, remains an elusive but much-desired capability with applications in various fields such as optical micromanipulation, imaging, and data communications, to name a few. In this work, we show analytically that it is possible to generate any desired scalar optical field with predefined amplitude and phase in 3D space, where the generated field is an exact duplicate of the desired field in case it is a solution of Helmholtz wave equation, or if the existence of such field is strictly forbidden, the generated field is the closest possible rendition of the desired field in amplitude and phase. The developed analytical approach is further supported via experimental demonstration of optical beams with exotic trajectories and can have a significant impact on the aforementioned application areas.
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8
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Wang D, Allcca AEL, Chung TF, Kildishev AV, Chen YP, Boltasseva A, Shalaev VM. Enhancing the graphene photocurrent using surface plasmons and a p-n junction. LIGHT, SCIENCE & APPLICATIONS 2020; 9:126. [PMID: 32704359 PMCID: PMC7371713 DOI: 10.1038/s41377-020-00344-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 05/27/2020] [Accepted: 06/08/2020] [Indexed: 05/23/2023]
Abstract
The recently proposed concept of graphene photodetectors offers remarkable properties such as unprecedented compactness, ultrabroadband detection, and an ultrafast response speed. However, owing to the low optical absorption of pristine monolayer graphene, the intrinsically low responsivity of graphene photodetectors significantly hinders the development of practical devices. To address this issue, numerous efforts have thus far been made to enhance the light-graphene interaction using plasmonic structures. These approaches, however, can be significantly advanced by leveraging the other critical aspect of graphene photoresponsivity enhancement-electrical junction control. It has been reported that the dominant photocarrier generation mechanism in graphene is the photothermoelectric (PTE) effect. Thus, the two energy conversion mechanisms involved in the graphene photodetection process are light-to-heat and heat-to-electricity conversions. In this work, we propose a meticulously designed device architecture to simultaneously enhance the two conversion efficiencies. Specifically, a gap plasmon structure is used to absorb a major portion of the incident light to induce localized heating, and a pair of split gates is used to produce a p-n junction in graphene to augment the PTE current generation. The gap plasmon structure and the split gates are designed to share common key components so that the proposed device architecture concurrently realizes both optical and electrical enhancements. We experimentally demonstrate the dominance of the PTE effect in graphene photocurrent generation and observe a 25-fold increase in the generated photocurrent compared to the un-enhanced cases. While further photocurrent enhancement can be achieved by applying a DC bias, the proposed device concept shows vast potential for practical applications.
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Affiliation(s)
- Di Wang
- School of Electrical and Computer Engineering, Purdue University, West Lafayette IN, 47907 USA
- Birck Nanotechnology Center, Purdue University, West Lafayette IN, 47907 USA
| | - Andres E. Llacsahuanga Allcca
- Birck Nanotechnology Center, Purdue University, West Lafayette IN, 47907 USA
- Department of Physics and Astronomy, Purdue University, West Lafayette IN, 47907 USA
| | - Ting-Fung Chung
- Birck Nanotechnology Center, Purdue University, West Lafayette IN, 47907 USA
- Department of Physics and Astronomy, Purdue University, West Lafayette IN, 47907 USA
| | - Alexander V. Kildishev
- School of Electrical and Computer Engineering, Purdue University, West Lafayette IN, 47907 USA
- Birck Nanotechnology Center, Purdue University, West Lafayette IN, 47907 USA
- Purdue Quantum Science and Engineering Institute (PQSEI), Purdue University, West Lafayette IN, 47907 USA
| | - Yong P. Chen
- School of Electrical and Computer Engineering, Purdue University, West Lafayette IN, 47907 USA
- Birck Nanotechnology Center, Purdue University, West Lafayette IN, 47907 USA
- Department of Physics and Astronomy, Purdue University, West Lafayette IN, 47907 USA
- Purdue Quantum Science and Engineering Institute (PQSEI), Purdue University, West Lafayette IN, 47907 USA
| | - Alexandra Boltasseva
- School of Electrical and Computer Engineering, Purdue University, West Lafayette IN, 47907 USA
- Birck Nanotechnology Center, Purdue University, West Lafayette IN, 47907 USA
- Purdue Quantum Science and Engineering Institute (PQSEI), Purdue University, West Lafayette IN, 47907 USA
| | - Vladimir M. Shalaev
- School of Electrical and Computer Engineering, Purdue University, West Lafayette IN, 47907 USA
- Birck Nanotechnology Center, Purdue University, West Lafayette IN, 47907 USA
- Purdue Quantum Science and Engineering Institute (PQSEI), Purdue University, West Lafayette IN, 47907 USA
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9
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Li L, Jiang Y, Jiang P, Li X, Qiu Y, Jia P, Pi Z, Hu Y, Chen Z, Xu J. Experimental observation of three-dimensional non-paraxial accelerating beams. OPTICS EXPRESS 2020; 28:17653-17659. [PMID: 32679970 DOI: 10.1364/oe.387866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 05/20/2020] [Indexed: 06/11/2023]
Abstract
We experimentally realize three-dimensional non-paraxial accelerating beams associated with different coordinate systems. They are obtained by Fourier transforming a phase-modulated wave front in an aberration-compensated system. The phase pattern is encoded to include the phase and amplitude modulation for the accelerating beams with additional correction phase for the aberration compensation. These beams propagate along a circular trajectory, but they exhibit rather complex intensity patterns corresponding to the shape-invariant solutions in parabolic, prolate spheroidal and oblate spheroidal coordinate systems.
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10
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McClung A, Mansouree M, Arbabi A. At-will chromatic dispersion by prescribing light trajectories with cascaded metasurfaces. LIGHT, SCIENCE & APPLICATIONS 2020; 9:93. [PMID: 32528667 PMCID: PMC7253474 DOI: 10.1038/s41377-020-0335-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 05/10/2020] [Accepted: 05/12/2020] [Indexed: 05/22/2023]
Abstract
Chromatic dispersion spatially separates white light into colours, producing rainbows and similar effects. Detrimental to imaging but essential to spectroscopy, chromatic dispersion is the result of material properties in refractive optics and is considered an inherent characteristic of diffractive devices such as gratings and flat lenses. Here, we present a fundamental relation connecting an optical system's dispersion to the trajectories light takes through it and show that arbitrary control over dispersion may be achieved by prescribing specific trajectories, even in diffractive systems. Using cascaded metasurfaces (2D arrays of sub-micron scatterers) to direct light along predetermined trajectories, we present an achromatic twisted metalens and experimentally demonstrate beam deflectors with arbitrary dispersion. This new insight and design approach usher in a new class of optical systems with wide-ranging applications.
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Affiliation(s)
- Andrew McClung
- Department of Electrical and Computer Engineering, University of Massachusetts Amherst, 151 Holdsworth Way, Amherst, MA 01003 USA
| | - Mahdad Mansouree
- Department of Electrical and Computer Engineering, University of Massachusetts Amherst, 151 Holdsworth Way, Amherst, MA 01003 USA
| | - Amir Arbabi
- Department of Electrical and Computer Engineering, University of Massachusetts Amherst, 151 Holdsworth Way, Amherst, MA 01003 USA
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11
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Jiang J, Lupoiu R, Wang EW, Sell D, Paul Hugonin J, Lalanne P, Fan JA. MetaNet: a new paradigm for data sharing in photonics research. OPTICS EXPRESS 2020; 28:13670-13681. [PMID: 32403837 DOI: 10.1364/oe.388378] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 04/14/2020] [Indexed: 06/11/2023]
Abstract
Optimization methods are playing an increasingly important role in all facets of photonics engineering, from integrated photonics to free space diffractive optics. However, efforts in the photonics community to develop optimization algorithms remain uncoordinated, which has hindered proper benchmarking of design approaches and access to device designs based on optimization. We introduce MetaNet, an online database of photonic devices and design codes intended to promote coordination and collaboration within the photonics community. Using metagratings as a model system, we have uploaded over one hundred thousand device layouts to the database, as well as source code for implementations of local and global topology optimization methods. Further analyses of these large datasets allow the distribution of optimized devices to be visualized for a given optimization method. We expect that the coordinated research efforts enabled by MetaNet will expedite algorithm development for photonics design.
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12
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Zhang C, Divitt S, Fan Q, Zhu W, Agrawal A, Lu Y, Xu T, Lezec HJ. Low-loss metasurface optics down to the deep ultraviolet region. LIGHT, SCIENCE & APPLICATIONS 2020; 9:55. [PMID: 32284857 PMCID: PMC7142140 DOI: 10.1038/s41377-020-0287-y] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 02/25/2020] [Accepted: 03/11/2020] [Indexed: 05/05/2023]
Abstract
Shrinking conventional optical systems to chip-scale dimensions will benefit custom applications in imaging, displaying, sensing, spectroscopy, and metrology. Towards this goal, metasurfaces-planar arrays of subwavelength electromagnetic structures that collectively mimic the functionality of thicker conventional optical elements-have been exploited at frequencies ranging from the microwave range up to the visible range. Here, we demonstrate high-performance metasurface optical components that operate at ultraviolet wavelengths, including wavelengths down to the record-short deep ultraviolet range, and perform representative wavefront shaping functions, namely, high-numerical-aperture lensing, accelerating beam generation, and hologram projection. The constituent nanostructured elements of the metasurfaces are formed of hafnium oxide-a loss-less, high-refractive-index dielectric material deposited using low-temperature atomic layer deposition and patterned using high-aspect-ratio Damascene lithography. This study opens the way towards low-form factor, multifunctional ultraviolet nanophotonic platforms based on flat optical components, enabling diverse applications including lithography, imaging, spectroscopy, and quantum information processing.
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Affiliation(s)
- Cheng Zhang
- School of Optical and Electronic Information & Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, 430074 Wuhan, China
- Physical Measurement Laboratory, National Institute of Standards and Technology, 20899 Gaithersburg, MD USA
- Maryland Nanocenter, University of Maryland, College Park, MD 20742 USA
| | - Shawn Divitt
- Physical Measurement Laboratory, National Institute of Standards and Technology, 20899 Gaithersburg, MD USA
- Maryland Nanocenter, University of Maryland, College Park, MD 20742 USA
| | - Qingbin Fan
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 210093 Nanjing, China
| | - Wenqi Zhu
- Physical Measurement Laboratory, National Institute of Standards and Technology, 20899 Gaithersburg, MD USA
- Maryland Nanocenter, University of Maryland, College Park, MD 20742 USA
| | - Amit Agrawal
- Physical Measurement Laboratory, National Institute of Standards and Technology, 20899 Gaithersburg, MD USA
- Maryland Nanocenter, University of Maryland, College Park, MD 20742 USA
| | - Yanqing Lu
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 210093 Nanjing, China
| | - Ting Xu
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 210093 Nanjing, China
| | - Henri J. Lezec
- Physical Measurement Laboratory, National Institute of Standards and Technology, 20899 Gaithersburg, MD USA
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13
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Miscuglio M, Borys NJ, Spirito D, Martín-García B, Zaccaria RP, Weber-Bargioni A, Schuck PJ, Krahne R. Planar Aperiodic Arrays as Metasurfaces for Optical Near-Field Patterning. ACS NANO 2019; 13:5646-5654. [PMID: 31021592 DOI: 10.1021/acsnano.9b00821] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Plasmonic metasurfaces have spawned the field of flat optics using nanostructured planar metallic or dielectric surfaces that can replace bulky optical elements and enhance the capabilities of traditional far-field optics. Furthermore, the potential of flat optics can go far beyond far-field modulation and can be exploited for functionality in the near-field itself. Here, we design metasurfaces based on aperiodic arrays of plasmonic Au nanostructures for tailoring the optical near-field in the visible and near-infrared spectral range. The basic element of the arrays is a rhomboid that is modulated in size, orientation, and position to achieve the desired functionality of the micron-size metasurface structure. Using two-photon-photoluminescence as a tool to probe the near-field profiles in the plane of the metasurfaces, we demonstrate the molding of light into different near-field intensity patterns and active pattern control via the far-field illumination. Finite element method simulations reveal that the near-field modulation occurs via a combination of the plasmonic resonances of the rhomboids and field enhancement in the nanoscale gaps in between the elements. This approach enables optical elements that can switch the near-field distribution across the metasurface via wavelength and polarization of the incident far-field light and provides pathways for light matter interaction in integrated devices.
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Affiliation(s)
- Mario Miscuglio
- Istituto Italiano di Tecnologia , Via Morego 30 , 16163 Genova , Italy
- Dipartimento di Chimica e Chimica Industriale , Università degli Studi di Genova , Via Dodecaneso, 31 , 16146 Genova , Italy
| | - Nicholas J Borys
- Molecular Foundry , Lawrence Berkeley National Lab , 1 Cyclotron Road , Berkeley , California 94720 , United States
| | - Davide Spirito
- Istituto Italiano di Tecnologia , Via Morego 30 , 16163 Genova , Italy
| | | | | | - Alexander Weber-Bargioni
- Molecular Foundry , Lawrence Berkeley National Lab , 1 Cyclotron Road , Berkeley , California 94720 , United States
| | - P James Schuck
- Molecular Foundry , Lawrence Berkeley National Lab , 1 Cyclotron Road , Berkeley , California 94720 , United States
| | - Roman Krahne
- Istituto Italiano di Tecnologia , Via Morego 30 , 16163 Genova , Italy
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14
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Fan Q, Zhu W, Liang Y, Huo P, Zhang C, Agrawal A, Luo X, Lu Y, Qiu C, Lezec H, Xu T. Broadband Generation of Photonic Spin-Controlled Arbitrary Accelerating Light Beams in the Visible. NANO LETTERS 2019; 19:1158-1165. [PMID: 30595022 PMCID: PMC6536309 DOI: 10.1021/acs.nanolett.8b04571] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Bending light along arbitrary curvatures is a captivating and popular notion, triggering unprecedented endeavors in achieving diffraction-free propagation along a curved path in free-space. Much effort has been devoted to achieving this goal in homogeneous space, which solely relies on the transverse acceleration of beam centroid exerted by a beam generator. Here, based on an all-dielectric metasurface, we experimentally report a synthetic strategy of encoding and multiplexing acceleration features on a freely propagating light beam, synergized with photonic spin states of light. Independent switching between two arbitrary visible accelerating light beams with distinct acceleration directions and caustic trajectories is achieved. This proof-of-concept recipe demonstrates the strength of the designed metasurface chip: subwavelength pixel size, independent control over light beam curvature, broadband operation in the visible, and ultrathin scalable planar architecture. Our results open up the possibility of creating ultracompact, high-pixel density, and flat-profile nanophotonic platforms for efficient generation and dynamical control of structured light beams.
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Affiliation(s)
- Qingbin Fan
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Wenqi Zhu
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
- Maryland NanoCenter, University of Maryland, College Park, MD 20742, USA
| | - Yuzhang Liang
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Pengcheng Huo
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Cheng Zhang
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
- Maryland NanoCenter, University of Maryland, College Park, MD 20742, USA
| | - Amit Agrawal
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
- Maryland NanoCenter, University of Maryland, College Park, MD 20742, USA
| | - Xiangang Luo
- Institute of Optics and Electronics, Chinese Academy of Sciences, Chengdu 610209, China
| | - Yanqing Lu
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Chengwei Qiu
- Department of Electrical and Computer Engineering, National University of Singapore, 117583, Singapore
- , ,
| | - Henri Lezec
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
- , ,
| | - Ting Xu
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
- , ,
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15
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Xing E, Gao H, Rong J, Khew SY, Liu H, Tong C, Hong M. Dynamically tunable multi-lobe laser generation via multifocal curved beam. OPTICS EXPRESS 2018; 26:30944-30951. [PMID: 30469984 DOI: 10.1364/oe.26.030944] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 10/15/2018] [Indexed: 06/09/2023]
Abstract
Beams with curved properties, represented by Airy beam, have already shown potential applications in various fields. Here we propose a simple method to achieve a multifocal curved beam (MCB). The scheme is based on the ability of microspheres to control the distribution of the light field. Combined with the caustic effect, the dynamic control of the beam curvature and the foci can be realized. The simulation results confirm the mechanism behind this phenomenon. Furthermore, MCB is applied experimentally into the end-pumped microchip laser. This work has verified the theory of MCB and achieved a dynamically tunable multi-lobe laser, which has a wide application prospect.
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Henstridge M, Pfeiffer C, Wang D, Boltasseva A, Shalaev VM, Grbic A, Merlin R. Synchrotron radiation from an accelerating light pulse. Science 2018; 362:439-442. [DOI: 10.1126/science.aat5915] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 08/30/2018] [Indexed: 11/02/2022]
Abstract
Synchrotron radiation—namely, electromagnetic radiation produced by charges moving in a curved path—is regularly generated at large-scale facilities where giga–electron volt electrons move along kilometer-long circular paths. We use a metasurface to bend light and demonstrate synchrotron radiation produced by a subpicosecond pulse, which moves along a circular arc of radius 100 micrometers inside a nonlinear crystal. The emitted radiation, in the terahertz frequency range, results from the nonlinear polarization induced by the pulse. The generation of synchrotron radiation from a pulse revolving about a circular trajectory holds promise for the development of on-chip terahertz sources.
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