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Zhao X, Liang H, Ren L, Pang X. Optical skyrmion and its "zipper-like" topological behavior in an energy flux field. OPTICS LETTERS 2024; 49:5391-5394. [PMID: 39352963 DOI: 10.1364/ol.537923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2024] [Accepted: 09/03/2024] [Indexed: 10/04/2024]
Abstract
The optical skyrmion and its topological behavior are analyzed in an energy flux field constructed by an X-type vortex in a high numerical aperture system. The conditions for the formation of a skyrmion structure in this field are discussed, showing that the vortex pattern of the transverse energy flow and the inverse energy flow are crucial for the skyrmions and also are controlled by the phase gradient of the X-type vortex. Notably, the "zipper-like" topological reaction, which is the first, to our knowledge, found in ferromagnetic materials, is observed, and the physical mechanism is also explained by the relation of orbital angular momentum density and Poynting vectors. The results will reach the topological theory and may have applications in optical traps and data storage.
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Wang S, Zhou Z, Zheng Z, Sun J, Cao H, Song S, Deng ZL, Qin F, Cao Y, Li X. Topological Structures of Energy Flow: Poynting Vector Skyrmions. PHYSICAL REVIEW LETTERS 2024; 133:073802. [PMID: 39213555 DOI: 10.1103/physrevlett.133.073802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/29/2024] [Accepted: 07/16/2024] [Indexed: 09/04/2024]
Abstract
Topological properties of energy flow of light are fundamentally interesting and may introduce novel physical phenomena associated with directional light scattering and optical trapping. In this Letter, skyrmionlike structures formed by Poynting vectors are unveiled in the focal region of two pairs of counterpropagating cylindrical vector vortex beams in free space. The appearance of local phase singularities, and the distinct traveling and standing wave modes of different field components passing through the focal spot lead to a Néel-Bloch-Néel transition of Poynting vector skyrmion textures along the light propagating direction. By shaping the wave front of the incident beams with patterned amplitudes, the topological invariant of the Poynting vector skyrmions can be further tuned in a prospective area. This work expands the family of optical skyrmions and holds great potential in energy flow associated applications.
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Affiliation(s)
- Sicong Wang
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China and College of Physics & Optoelectronic Engineering, Jinan University, Guangzhou 510632, China
| | - Zhikai Zhou
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China and College of Physics & Optoelectronic Engineering, Jinan University, Guangzhou 510632, China
| | - Zecan Zheng
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China and College of Physics & Optoelectronic Engineering, Jinan University, Guangzhou 510632, China
| | - Jialin Sun
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China and College of Physics & Optoelectronic Engineering, Jinan University, Guangzhou 510632, China
| | - Hongkun Cao
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China and College of Physics & Optoelectronic Engineering, Jinan University, Guangzhou 510632, China
| | - Shichao Song
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China and College of Physics & Optoelectronic Engineering, Jinan University, Guangzhou 510632, China
| | - Zi-Lan Deng
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China and College of Physics & Optoelectronic Engineering, Jinan University, Guangzhou 510632, China
| | - Fei Qin
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China and College of Physics & Optoelectronic Engineering, Jinan University, Guangzhou 510632, China
| | - Yaoyu Cao
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China and College of Physics & Optoelectronic Engineering, Jinan University, Guangzhou 510632, China
| | - Xiangping Li
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China and College of Physics & Optoelectronic Engineering, Jinan University, Guangzhou 510632, China
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3
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Shen Y, Papasimakis N, Zheludev NI. Nondiffracting supertoroidal pulses and optical "Kármán vortex streets". Nat Commun 2024; 15:4863. [PMID: 38849349 PMCID: PMC11161654 DOI: 10.1038/s41467-024-48927-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 05/16/2024] [Indexed: 06/09/2024] Open
Abstract
Supertoroidal light pulses, as space-time nonseparable electromagnetic waves, exhibit unique topological properties including skyrmionic configurations, fractal-like singularities, and energy backflow in free space, which however do not survive upon propagation. Here, we introduce the non-diffracting supertoroidal pulses (NDSTPs) with propagation-robust skyrmionic and vortex field configurations that persists over arbitrary propagation distances. Intriguingly, the field structure of NDSTPs has a similarity with the von Kármán vortex street, a pattern of swirling vortices in fluid and gas dynamics with staggered singularities that can stably propagate forward. NDSTPs will be of interest as directed channels for information and energy transfer applications.
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Affiliation(s)
- Yijie Shen
- Centre for Disruptive Photonic Technologies, School of Physical and Mathematical Sciences & The Photonics Institute, Nanyang Technological University, Singapore, 637378, Singapore.
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, 639798, Singapore.
| | - Nikitas Papasimakis
- Optoelectronics Research Centre & Centre for Photonic Metamaterials, University of Southampton, Southampton, SO17 1BJ, UK
| | - Nikolay I Zheludev
- Centre for Disruptive Photonic Technologies, School of Physical and Mathematical Sciences & The Photonics Institute, Nanyang Technological University, Singapore, 637378, Singapore
- Optoelectronics Research Centre & Centre for Photonic Metamaterials, University of Southampton, Southampton, SO17 1BJ, UK
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4
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Fu T, Zhang RY, Jia S, Chan CT, Wang S. Near-Field Spin Chern Number Quantized by Real-Space Topology of Optical Structures. PHYSICAL REVIEW LETTERS 2024; 132:233801. [PMID: 38905648 DOI: 10.1103/physrevlett.132.233801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 05/01/2024] [Indexed: 06/23/2024]
Abstract
The Chern number has been widely used to describe the topological properties of periodic structures in momentum space. Here, we introduce a real-space spin Chern number for the optical near fields of finite-sized structures. This new spin Chern number is intrinsically quantized and equal to the structure's Euler characteristic. The relationship is robust against continuous deformation of the structure's geometry and is irrelevant to the specific material constituents or external excitation. Our Letter enriches topological physics by extending the Chern number to real space, opening exciting possibilities for exploring the real-space topological properties of light.
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Lin Q, Feng F, Cai Y, Lu X, Zeng X, Wang C, Xu S, Li J, Yuan X. Direct space-time manipulation mechanism for spatio-temporal coupling of ultrafast light field. Nat Commun 2024; 15:2416. [PMID: 38499570 PMCID: PMC10948815 DOI: 10.1038/s41467-024-46802-x] [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: 07/09/2023] [Accepted: 03/11/2024] [Indexed: 03/20/2024] Open
Abstract
Traditionally, manipulation of spatiotemporal coupling (STC) of the ultrafast light fields can be actualized in the space-spectrum domain with some 4-f pulse shapers, which suffers usually from some limitations, such as spectral/pixel resolution and information crosstalk associated with the 4-f pulse shapers. This work introduces a novel mechanism for direct space-time manipulation of ultrafast light fields to overcome the limitations. This mechanism combines a space-dependent time delay with some spatial geometrical transformations, which has been experimentally proved by generating a high-quality STC light field, called light spring (LS). The LS, owing a broad topological charge bandwidth of 11.5 and a tunable central topological charge from 2 to -11, can propagate with a stable spatiotemporal intensity structure from near to far fields. This achievement implies the mechanism provides an efficient way to generate complex STC light fields, such as LS with potential applications in information encryption, optical communication, and laser-plasma acceleration.
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Affiliation(s)
- Qinggang Lin
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, 518060, Shenzhen, China
| | - Fu Feng
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, 518060, Shenzhen, China
- Research Center for Humanoid Sensing, Zhejiang Laboratory, 311100, Hangzhou, China
| | - Yi Cai
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, 518060, Shenzhen, China
| | - Xiaowei Lu
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, 518060, Shenzhen, China
| | - Xuanke Zeng
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, 518060, Shenzhen, China
| | - Congying Wang
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, 518060, Shenzhen, China
| | - Shixiang Xu
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, 518060, Shenzhen, China.
| | - Jingzhen Li
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, 518060, Shenzhen, China
| | - Xiaocong Yuan
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, 518060, Shenzhen, China.
- Research Center for Humanoid Sensing, Zhejiang Laboratory, 311100, Hangzhou, China.
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Smirnova DA, Nori F, Bliokh KY. Water-Wave Vortices and Skyrmions. PHYSICAL REVIEW LETTERS 2024; 132:054003. [PMID: 38364154 DOI: 10.1103/physrevlett.132.054003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 11/14/2023] [Indexed: 02/18/2024]
Abstract
Topological wave structures-phase vortices, skyrmions, merons, etc.-are attracting enormous attention in a variety of quantum and classical wave fields. Surprisingly, these structures have never been properly explored in the most obvious example of classical waves: water-surface (gravity-capillary) waves. Here, we fill this gap and describe (i) water-wave vortices of different orders carrying quantized angular momentum with orbital and spin contributions, (ii) skyrmion lattices formed by the instantaneous displacements of the water-surface particles in wave interference, and (iii) meron (half-skyrmion) lattices formed by the spin-density vectors, as well as (iv) spatiotemporal water-wave vortices and skyrmions. We show that all these topological entities can be readily generated in linear water-wave interference experiments. Our findings can find applications in microfluidics and show that water waves can be employed as an attainable playground for emulating universal topological wave phenomena.
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Affiliation(s)
- Daria A Smirnova
- Theoretical Quantum Physics Laboratory, Cluster for Pioneering Research, RIKEN, Wako-shi, Saitama 351-0198, Japan
- Research School of Physics, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Franco Nori
- Theoretical Quantum Physics Laboratory, Cluster for Pioneering Research, RIKEN, Wako-shi, Saitama 351-0198, Japan
- Center for Quantum Computing (RQC), RIKEN, Wako-shi, Saitama 351-0198, Japan
- Physics Department, University of Michigan, Ann Arbor, Michigan 48109-1040, USA
| | - Konstantin Y Bliokh
- Theoretical Quantum Physics Laboratory, Cluster for Pioneering Research, RIKEN, Wako-shi, Saitama 351-0198, Japan
- Centre of Excellence ENSEMBLE3 Sp. z o.o., 01-919 Warsaw, Poland
- Donostia International Physics Center (DIPC), Donostia-San Sebastián 20018, Spain
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7
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Cao S, Du L, Shi P, Yuan X. Topological state transitions of skyrmionic beams under focusing configurations. OPTICS EXPRESS 2024; 32:4167-4179. [PMID: 38297623 DOI: 10.1364/oe.514440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 01/11/2024] [Indexed: 02/02/2024]
Abstract
The recent emerging appearance of optical analogs of magnetic quasiparticles, i.e., optical skyrmions constructed via spin, field, and Stokes vectors, has garnered substantial interest from deep-subwavelength imaging and quantum entanglement. Here, we investigate systematically the topological state transitions of skyrmionic beams constructed by the Stokes vectors in the focusing configuration. We theoretically demonstrated that in the weak focusing, the skyrmion topological number is protected. Whereas, in the tight focusing, a unique topological transformation with skyrmion number variation is exhibited for the optical skyrmion, anti-skyrmion, and 2nd-order skyrmion structures. The significant difference between the topological state transitions of these two cases originates from the transformation from the paraxial optical system to the nonparaxial optical system, and the approximate two-dimensional polarization structure to the three-dimensional polarization structure. The results provide new insights into the topological state transitions in topological structures, which promote applications in information processing, data storage, and free-space optical communications.
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Zhang YC, Zhao LM, Zhou YS. Modulation of photonic skyrmions in a thin metal film structure. OPTICS EXPRESS 2024; 32:3157-3166. [PMID: 38297543 DOI: 10.1364/oe.510711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 01/02/2024] [Indexed: 02/02/2024]
Abstract
Photonic skyrmions have been a hot topic in recent years. However, modulating the spin distributions of the skyrmions is still a challenging topic. In this paper, we investigate the detailed spin distributions of photonic skyrmions in thin metal film sandwiched by different dielectrics. We find that the ratios of different spin components can be adjusted by the thickness of the metal film, while the absolute value of total spin can be controlled by the frequency of the light source. Therefore, by choosing proper metal thickness in the preparation process and certain beam frequency in actual experiment, we can get the exact type of spin distribution we prefer. In addition, when the dielectric layers are arranged asymmetrically, the spin distributions can also be modulated significantly by adjustig the ratio of the dielectric constants of the upper and lower dielectric layers. Our results provide a new pathway for the modulation of photonic skyrmions.
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Lu C, Wang B, Fang X, Tsai DP, Zhu W, Song Q, Deng X, He T, Gong X, Luo H, Wang Z, Dai X, Shi Y, Cheng X. Nanoparticle Deep-Subwavelength Dynamics Empowered by Optical Meron-Antimeron Topology. NANO LETTERS 2024; 24:104-113. [PMID: 37943097 DOI: 10.1021/acs.nanolett.3c03351] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
Optical meron is a type of nonplanar topological texture mainly observed in surface plasmon polaritons and highly symmetric points of photonic crystals in the reciprocal space. Here, we report Poynting-vector merons formed at the real space of a photonic crystal for a Γ-point illumination. Optical merons can be utilized for subwavelength-resolution manipulation of nanoparticles, resembling a topological Hall effect on electrons via magnetic merons. In particular, staggered merons and antimerons impose strong radiation pressure on large gold nanoparticles (AuNPs), while focused hot spots in antimerons generate dominant optical gradient forces on small AuNPs. Synergistically, differently sized AuNPs in a still environment can be trapped or orbit in opposite directions, mimicking a coupled galaxy system. They can also be separated with a 10 nm precision when applying a flow velocity of >1 mm/s. Our study unravels a novel way to exploit topological textures for optical manipulation with deep-subwavelength precision and switchable topology in a lossless environment.
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Affiliation(s)
- Chengfeng Lu
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
- Technology Innovation Center of Mass Spectrometry for State Market Regulation, Center for Advanced Measurement Science, National Institute of Metrology, Beijing 100029, China
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai 200092, China
- Shanghai Institute of Intelligent Science and Technology, Tongji University, Shanghai 200092, China
- Shanghai Frontiers Science Center of Digital Optics, Shanghai 200092, China
| | - Bo Wang
- State Key Laboratory of Advanced Optical Communication Systems and Networks, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiang Fang
- Technology Innovation Center of Mass Spectrometry for State Market Regulation, Center for Advanced Measurement Science, National Institute of Metrology, Beijing 100029, China
| | - Din Ping Tsai
- Department of Electrical Engineering, City University of Hong Kong, Kowloon 999077, Hong Kong
| | - Weiming Zhu
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Qinghua Song
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Xiao Deng
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai 200092, China
- Shanghai Institute of Intelligent Science and Technology, Tongji University, Shanghai 200092, China
- Shanghai Frontiers Science Center of Digital Optics, Shanghai 200092, China
| | - Tao He
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai 200092, China
- Shanghai Institute of Intelligent Science and Technology, Tongji University, Shanghai 200092, China
- Shanghai Frontiers Science Center of Digital Optics, Shanghai 200092, China
| | - Xiaoyun Gong
- Technology Innovation Center of Mass Spectrometry for State Market Regulation, Center for Advanced Measurement Science, National Institute of Metrology, Beijing 100029, China
| | - Hong Luo
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
- Technology Innovation Center of Mass Spectrometry for State Market Regulation, Center for Advanced Measurement Science, National Institute of Metrology, Beijing 100029, China
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai 200092, China
- Shanghai Institute of Intelligent Science and Technology, Tongji University, Shanghai 200092, China
- Shanghai Frontiers Science Center of Digital Optics, Shanghai 200092, China
| | - Zhanshan Wang
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai 200092, China
- Shanghai Institute of Intelligent Science and Technology, Tongji University, Shanghai 200092, China
- Shanghai Frontiers Science Center of Digital Optics, Shanghai 200092, China
| | - Xinhua Dai
- Technology Innovation Center of Mass Spectrometry for State Market Regulation, Center for Advanced Measurement Science, National Institute of Metrology, Beijing 100029, China
| | - Yuzhi Shi
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai 200092, China
- Shanghai Institute of Intelligent Science and Technology, Tongji University, Shanghai 200092, China
- Shanghai Frontiers Science Center of Digital Optics, Shanghai 200092, China
| | - Xinbin Cheng
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai 200092, China
- Shanghai Institute of Intelligent Science and Technology, Tongji University, Shanghai 200092, China
- Shanghai Frontiers Science Center of Digital Optics, Shanghai 200092, China
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10
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Wang H, Fan S. Photonic Spin Hopfions and Monopole Loops. PHYSICAL REVIEW LETTERS 2023; 131:263801. [PMID: 38215381 DOI: 10.1103/physrevlett.131.263801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 11/28/2023] [Indexed: 01/14/2024]
Abstract
Spin textures with various topological orders are of great theoretical and practical interest. Hopfion, a spin texture characterized by a three-dimensional topological order was recently realized in electronic spin systems. Here, we show that monochromatic light can be structured such that its photonic spin exhibits a hopfion texture in the three-dimensional real space. We also provide ways to construct spin textures of arbitrary Hopf charges. When extending the system to four dimensions by introducing a parameter dimension, a new type of topological defect in the form of a monopole loop in photonic spin is encountered. Each point on the loop is a topological spin defect in three dimensions, and the loop itself carries quantized Hopf charges. Such photonic spin texture and defect may find application in control and sensing of nanoparticles, and optical generation of topological texture in motions of particles or fluids.
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Affiliation(s)
- Haiwen Wang
- Department of Applied Physics, Stanford University, Stanford, California 94305, USA
| | - Shanhui Fan
- Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA
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11
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Zhang H, Sun Y, Huang J, Wu B, Yang Z, Bliokh KY, Ruan Z. Topologically crafted spatiotemporal vortices in acoustics. Nat Commun 2023; 14:6238. [PMID: 37803024 PMCID: PMC10558554 DOI: 10.1038/s41467-023-41776-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 09/15/2023] [Indexed: 10/08/2023] Open
Abstract
Vortices in fluids and gases have piqued the human interest for centuries. Development of classical-wave physics and quantum mechanics highlighted wave vortices characterized by phase singularities and topological charges. In particular, vortex beams have found numerous applications in modern optics and other areas. Recently, optical spatiotemporal vortex states exhibiting the phase singularity both in space and time have been described. Here, we report the topologically robust generation of acoustic spatiotemporal vortex pulses. We utilize an acoustic meta-grating with broken mirror symmetry which exhibits a topological phase transition with a pair of phase singularities with opposite topological charges emerging in the momentum-frequency domain. We show that these vortices are topologically robust against structural perturbations of the meta-grating and can be employed for the generation of spatiotemporal vortex pulses. Our work paves the way for studies and applications of spatiotemporal structured waves in acoustics and other wave systems.
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Affiliation(s)
- Hongliang Zhang
- School of Physics, Zhejiang Province Key Laboratory of Quantum Technology and Device, and State Key Laboratory for Extreme Photonics and Instrumentation, Zhejiang University, Hangzhou, 310027, China
| | - Yeyang Sun
- School of Physics, Zhejiang Province Key Laboratory of Quantum Technology and Device, and State Key Laboratory for Extreme Photonics and Instrumentation, Zhejiang University, Hangzhou, 310027, China
| | - Junyi Huang
- School of Physics, Zhejiang Province Key Laboratory of Quantum Technology and Device, and State Key Laboratory for Extreme Photonics and Instrumentation, Zhejiang University, Hangzhou, 310027, China
| | - Bingjun Wu
- School of Physics, Zhejiang Province Key Laboratory of Quantum Technology and Device, and State Key Laboratory for Extreme Photonics and Instrumentation, Zhejiang University, Hangzhou, 310027, China
| | - Zhaoju Yang
- School of Physics, Zhejiang Province Key Laboratory of Quantum Technology and Device, and State Key Laboratory for Extreme Photonics and Instrumentation, Zhejiang University, Hangzhou, 310027, China.
| | - Konstantin Y Bliokh
- Theoretical Quantum Physics Laboratory, Cluster for Pioneering Research, RIKEN, Wako-shi, Saitama, 351-0198, Japan
- Centre of Excellence ENSEMBLE3 Sp. z o.o., 01-919, Warsaw, Poland
- Donostia International Physics Center (DIPC), Donostia-San Sebastián, 20018, Spain
| | - Zhichao Ruan
- School of Physics, Zhejiang Province Key Laboratory of Quantum Technology and Device, and State Key Laboratory for Extreme Photonics and Instrumentation, Zhejiang University, Hangzhou, 310027, China.
- College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310027, China.
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12
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Tian B, Jiang J, Zheng Z, Wang X, Liu S, Huang W, Jiang T, Chen H, Deng S. Néel-type optical target skyrmions inherited from evanescent electromagnetic fields with rotational symmetry. NANOSCALE 2023; 15:13224-13232. [PMID: 37492006 DOI: 10.1039/d3nr02143b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/27/2023]
Abstract
Optical skyrmions have recently attracted growing interest due to their potential applications in deep-subwavelength imaging and nanometrology. While optical skyrmions have been successfully demonstrated using different field vectors, the study of their generation and control, as well as their general correlation with electromagnetic (EM) fields, is still in its infancy. Here, we theoretically propose that evanescent transverse-magnetic-polarized (TM-polarized) EM fields with rotational symmetry are actually Néel-type optical target skyrmions of the electric field vectors. Such optical target skyrmions are independent of the operation frequency and medium. Our proposal was verified by numerical simulations and real-space nano-imaging experiments performed on a graphene monolayer, where the target skyrmions could be as small as ∼100 nm in diameter. The results can therefore not only further our understanding of the formation mechanisms of EM topological textures, but also provide guidelines for the facile construction of EM skyrmions that may impact future information technologies.
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Affiliation(s)
- Bo Tian
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China.
| | - Jingyao Jiang
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China.
| | - Zebo Zheng
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China.
| | - Ximiao Wang
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China.
| | - Shaojing Liu
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China.
| | - Wuchao Huang
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China.
| | - Tian Jiang
- Institute for Quantum Information Science and Technology, College of Science, National University of Defense Technology, Changsha 410073, China.
| | - Huanjun Chen
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China.
| | - Shaozhi Deng
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China.
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13
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Luo X, Cai Y, Yue X, Zhang Y, Yun F, Li F. Full characterization of vector eigenstates in symmetrically confined systems with photonic spin-orbit coupling. OPTICS EXPRESS 2023; 31:27749-27760. [PMID: 37710843 DOI: 10.1364/oe.495899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 07/22/2023] [Indexed: 09/16/2023]
Abstract
The photonic spin-orbit (SO) coupling is a widely investigated effect in optical microcavities leading to various interesting physical phenomena and potential applications. We report the full sets of eigenenergies and eigenstates in a symmetrically confined potential under the effect of SO coupling induced by the transverse-electric transverse-magnetic (TE-TM) splitting, which are derived analytically via the degenerate perturbation theory. We obtained the eigenenergies and the eigenstates from the 1st to the 6th orders of excited manifold, and demonstrate unambiguously that universal rules governing the mode formation exist in such complicated photonic systems, making the modes exhibiting the features of solid and hollow skyrmions as well as spin vortices. We show that these eigenstates can be described by the SO coupled hyperspheres that can be decomposed into a series of higher-order Poincare spheres. Our results significantly extend the area of microcavity spin-optronics to the general theory of eigenvalues in confined systems, and provide an efficient theoretical frame for the information processing using microcavity-based high-dimensional vector states.
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14
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Jia F, Zhang Z, Cen L, Sun Y, Zhao Y. Same Wavelength Noise Filtering via Quantum Orbital Angular Momentum Emission. SENSORS (BASEL, SWITZERLAND) 2023; 23:7118. [PMID: 37631657 PMCID: PMC10458923 DOI: 10.3390/s23167118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 08/03/2023] [Accepted: 08/08/2023] [Indexed: 08/27/2023]
Abstract
In laser active detection, detection performance is affected by optical noise, laser interference, and environmental background interference. Conventional methods to filter optical noise take advantage of the differences between signal and noise in wavelength and polarization. Due to the limitations of traditional methods in the physical dimension, noise cannot be completely filtered out. In this manuscript, a new method of noise filtering based on the spatial distribution difference between the quantum orbital angular momentum beam and the background noise is proposed. The use of beams containing quantum orbital angular momentum can make the signal light have a new physical dimension and enrich the information of emitted light. We conduct a complete theoretical analysis and provide a proof-of-principle experiment. The experimental results are in good agreement with the theoretical analysis results, and there is a signal-to-noise ratio improvement of more than five times in laser active detection. Our method meets the urgent needs of laser active detection and can be applied in the field of high-quality target detection.
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Affiliation(s)
| | - Zijing Zhang
- School of Physics, Harbin Institute of Technology, Harbin 150001, China; (F.J.); (L.C.); (Y.S.)
| | | | | | - Yuan Zhao
- School of Physics, Harbin Institute of Technology, Harbin 150001, China; (F.J.); (L.C.); (Y.S.)
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15
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Toda Y, Tsuchiya S, Yamane K, Morita R, Oda M, Kurosawa T, Mertelj T, Mihailovic D. Optical vortex induced spatio-temporally modulated superconductivity in a high-T c cuprate. OPTICS EXPRESS 2023; 31:17537-17546. [PMID: 37381484 DOI: 10.1364/oe.487041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 04/25/2023] [Indexed: 06/30/2023]
Abstract
We report an experimental approach to produce spatially localized photoinduced superconducting state in a cuprate superconductor using optical vortices with ultrafast pulses. The measurements were carried out using coaxially aligned three-pulse time-resolved spectroscopy, in which an intense vortex pulse was used for coherent quenching of superconductivity and the resulting spatially modulated metastable states were analyzed by the pump-probe spectroscopy. The transient response after quenching shows a spatially localized superconducting state that remains unquenched at the dark core of the vortex beam for a few picoseconds. Because the quenching is instantaneously driven by photoexcited quasiparticles, the vortex beam profile can be transferred directly to the electron system. By using the optical vortex-induced superconductor, we demonstrate spatially resolved imaging of the superconducting response and show that the spatial resolution can be improved using the same principle as that of super-resolution microscopy for fluorescent molecules. The demonstration of spatially controlled photoinduced superconductivity is significant for establishing a new method for exploring novel photoinduced phenomena and applications in ultrafast optical devices.
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16
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Zheludev NI, Wilkowski D. The Rise of Toroidal Electrodynamics and Spectroscopy. ACS PHOTONICS 2023; 10:556-558. [PMID: 36942155 PMCID: PMC10021009 DOI: 10.1021/acsphotonics.2c01953] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Indexed: 06/18/2023]
Abstract
Toroidal electrodynamics is now massively influencing research in toroidal (Marinov et al. New J. Phys. 2007, 9, 234; Basharin et al. Phys. Rev. X 2015, 5, 011036; Jeong et al. ACS Photonics 2020, 7, 1699) and anapole metamaterials (Basharin et al. Phys. Rev. B 2017, 95, 035104; Wu et al. ACS Nano 2018, 12, 1920), optical properties of nanoparticles (Miroshnichenko et al. Nature Commun. 2015, 6, 8069; Gurvitz et al. Laser Photonics Rev. 2019, 13, 1800266), plasmonics (Ogut et al. Nano Lett. 2012, 12, 5239; Yezekyan et al. Nano Lett. 2022, 22, 6098), sensors (Gupta et al. Appl. Phys. Lett. 2017, 110, 121108; Ahmadivand et al. Mater. Today 2020, 32, 108; Wang et al. Nanophotonics 2021, 10, 1295; Yao et al. Photonix 2022, 3, 23), and lasers (Huang et al. Sci. Rep. 2013, 3, 1237; Hwang et al. Nanophotonics 2021, 10, 3599), while a recent publication on toroidal optical transitions in hydrogen-like atoms (Kuprov et al. Sci. Adv. 2022, 8, eabq7651) promises to launch a new chapter in spectroscopy. In this Viewpoint, we review these progresses.
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Affiliation(s)
- Nikolay I. Zheludev
- Optoelectronics
Research Centre, University of Southampton, Southampton, SO17 1BJ, United Kingdom
- Centre
for Disruptive Photonic Technologies, SPMS, The Photonics Institute, Nanyang Technological University, Singapore 637371, Singapore
- Hagler
Institute for Advanced Studies, Texas A&M
University, College Station, Texas 77843, United States
| | - David Wilkowski
- Centre
for Disruptive Photonic Technologies, SPMS, The Photonics Institute, Nanyang Technological University, Singapore 637371, Singapore
- Centre
for Quantum Technologies, National University
of Singapore, Singapore 117543, Singapore
- MajuLab,
International Joint Research Unit, UMI 3654, CNRS, Université
Côte d’Azur, Sorbonne Université, National University
of Singapore, Nanyang Technological University, Singapore 639798, Singapore
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17
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Abstract
AbstractOptical skyrmions have recently been constructed by tailoring vectorial near-field distributions through the interference of multiple surface plasmon polaritons, offering promising features for advanced information processing, transport and storage. Here, we provide experimental demonstration of electromagnetic skyrmions based on magnetic localized spoof plasmons (LSP) showing large topological robustness against continuous deformations, without stringent external interference conditions. By directly measuring the spatial profile of all three vectorial magnetic fields, we reveal multiple π-twist target skyrmion configurations mapped to multi-resonant near-equidistant LSP eigenmodes. The real-space skyrmion topology is robust against deformations of the meta-structure, demonstrating flexible skyrmionic textures for arbitrary shapes. The observed magnetic LSP skyrmions pave the way to ultra-compact and robust plasmonic devices, such as flexible sensors, wearable electronics and ultra-compact antennas.
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18
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Kuprov I, Wilkowski D, Zheludev N. Toroidal optical transitions in hydrogen-like atoms. SCIENCE ADVANCES 2022; 8:eabq6751. [PMID: 36351026 PMCID: PMC9645728 DOI: 10.1126/sciadv.abq6751] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
It is commonly believed that electromagnetic spectra of atoms and molecules can be fully described by interactions involving electric and magnetic multipoles. However, it has recently become clear that interactions between light and matter also involve toroidal multipoles-toroidal absorption lines have been observed in electromagnetic metamaterials. Here, we show that a previously unexplored type of spectroscopy of the hitherto largely neglected toroidal dipolar interaction becomes feasible if, apart from the classical r × r × p toroidal dipole density term responsible for the toroidal transitions in metamaterials, the spin-dependent r × σ term (which only occurs in relativistic quantum mechanics) is taken into account. Toroidal dipole operators are odd under parity and time-reversal symmetries; toroidal dipole transitions can therefore be distinguished from electric multipole and magnetic dipole transitions.
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Affiliation(s)
- Ilya Kuprov
- School of Chemistry, University of Southampton, Southampton, UK
| | - David Wilkowski
- Centre for Disruptive Photonic Technologies, SPMS, The Photonics Institute, Nanyang Technological University, Singapore 637371, Singapore
- Centre for Quantum Technologies, National University of Singapore, Singapore 117543, Singapore
- MajuLab, International Joint Research Unit IRL 3654, CNRS, Université Côte d’Azur, Sorbonne Université, National University of Singapore, Nanyang Technological University, Singapore, Singapore
| | - Nikolay Zheludev
- Centre for Disruptive Photonic Technologies, SPMS, The Photonics Institute, Nanyang Technological University, Singapore 637371, Singapore
- Optoelectronics Research Centre, University of Southampton, Southampton, UK
- Hagler Institute for Advanced Studies, Texas A&M University, College Station, TX 77843, USA
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Peng J, Zhang RY, Jia S, Liu W, Wang S. Topological near fields generated by topological structures. SCIENCE ADVANCES 2022; 8:eabq0910. [PMID: 36240266 PMCID: PMC9565808 DOI: 10.1126/sciadv.abq0910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 08/31/2022] [Indexed: 06/16/2023]
Abstract
The central idea of metamaterials and metaoptics is that, besides their base materials, the geometry of structures offers a broad extra dimension to explore for exotic functionalities. Here, we discover that the topology of structures fundamentally dictates the topological properties of optical fields and offers a new dimension to exploit for optical functionalities that are irrelevant to specific material constituents or structural geometries. We find that the nontrivial topology of metal structures ensures the birth of polarization singularities (PSs) in the near field with rich morphologies and intriguing spatial evolutions including merging, bifurcation, and topological transition. By mapping the PSs to non-Hermitian exceptional points and using homotopy theory, we extract the core invariant that governs the topological classification of the PSs and the conservation law that regulates their spatial evolutions. The results bridge singular optics, topological photonics, and non-Hermitian physics, with potential applications in chiral sensing, chiral quantum optics, and beyond photonics in other wave systems.
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Affiliation(s)
- Jie Peng
- Department of Physics, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Ruo-Yang Zhang
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Shiqi Jia
- Department of Physics, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Wei Liu
- College for Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha, Hunan 410073, China
| | - Shubo Wang
- Department of Physics, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, Guangdong 518057, China
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20
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Spontaneous generation and active manipulation of real-space optical vortices. Nature 2022; 611:48-54. [PMID: 36224392 DOI: 10.1038/s41586-022-05229-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 08/11/2022] [Indexed: 11/09/2022]
Abstract
Optical vortices are beams of light that carry orbital angular momentum1, which represents an extra degree of freedom that can be generated and manipulated for photonic applications2-8. Unlike vortices in other physical entities, the generation of optical vortices requires structural singularities9-12, but this affects their quasiparticle nature and hampers the possibility of altering their dynamics or making them interacting13-17. Here we report a platform that allows the spontaneous generation and active manipulation of an optical vortex-antivortex pair using an external field. An aluminium/silicon dioxide/nickel/silicon dioxide multilayer structure realizes a gradient-thickness optical cavity, where the magneto-optic effects of the nickel layer affect the transition between a trivial and a non-trivial topological phase. Rather than a structural singularity, the vortex-antivortex pairs present in the light reflected by our device are generated through mathematical singularities in the generalized parameter space of the top and bottom silicon dioxide layers, which can be mapped onto real space and exhibit polarization-dependent and topology-dependent dynamics driven by external magnetic fields. We expect that the field-induced engineering of optical vortices that we report will facilitate the study of topological photonic interactions and inspire further efforts to bestow quasiparticle-like properties to various topological photonic textures such as toroidal vortices, polarization and vortex knots, and optical skyrmions.
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21
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Wang C, Liu J, Zhang Z. Transmission characteristics of femtosecond laser pulses in a polymer waveguide. OPTICS EXPRESS 2022; 30:31396-31406. [PMID: 36242222 DOI: 10.1364/oe.467884] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 08/02/2022] [Indexed: 06/16/2023]
Abstract
Femtosecond lasers have been widely employed in scientific and industrial applications, including the study of material properties, fabrication of structures on the sub-micrometer scale, surgical and medical treatment, etc. In these applications, the ultrafast laser is implemented either in free space or via an optical fiber-based channel. To investigate the light-matter interaction on a chip-based dimension, laser pulses with extremely high peak power need to be injected into an integrated optical waveguide. This requires the waveguide to be transparent and linear at this power, but also capable of providing a highly efficient and reliable interface for fiber-chip coupling. Contrary to the common belief that polymer materials may suffer from stability issues, we show that a polymer waveguide fabricated under simple and low-cost technology using only commercial materials can indeed transmit femtosecond laser pulses with similar characteristics as low-power continuous-wave laser. The coupling efficiency with a lensed fiber is ∼76% per facet. The pulse broadening effect in the polymer waveguide is also well fitted by the material and waveguide dispersion without nonlinear behavior. This study paves the way for developing a low-cost, highly efficient, polymer-based waveguide platform for the investigation of ultrafast phenomena on a chip.
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22
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He C, Shen Y, Forbes A. Towards higher-dimensional structured light. LIGHT, SCIENCE & APPLICATIONS 2022; 11:205. [PMID: 35790711 PMCID: PMC9256673 DOI: 10.1038/s41377-022-00897-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 06/12/2022] [Accepted: 06/16/2022] [Indexed: 05/17/2023]
Abstract
Structured light refers to the arbitrarily tailoring of optical fields in all their degrees of freedom (DoFs), from spatial to temporal. Although orbital angular momentum (OAM) is perhaps the most topical example, and celebrating 30 years since its connection to the spatial structure of light, control over other DoFs is slowly gaining traction, promising access to higher-dimensional forms of structured light. Nevertheless, harnessing these new DoFs in quantum and classical states remains challenging, with the toolkit still in its infancy. In this perspective, we discuss methods, challenges, and opportunities for the creation, detection, and control of multiple DoFs for higher-dimensional structured light. We present a roadmap for future development trends, from fundamental research to applications, concentrating on the potential for larger-capacity, higher-security information processing and communication, and beyond.
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Affiliation(s)
- Chao He
- Department of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ, UK.
| | - Yijie Shen
- Optoelectronics Research Centre, University of Southampton, Southampton, SO17 1BJ, UK.
| | - Andrew Forbes
- School of Physics, University of the Witwatersrand, Private Bag 3, Johannesburg, 2050, South Africa.
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23
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Shi P, Lei X, Zhang Q, Li H, Du L, Yuan X. Intrinsic Spin-Momentum Dynamics of Surface Electromagnetic Waves in Dispersive Interfaces. PHYSICAL REVIEW LETTERS 2022; 128:213904. [PMID: 35687452 DOI: 10.1103/physrevlett.128.213904] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 04/26/2022] [Indexed: 06/15/2023]
Abstract
Intrinsic spin-momentum locking is an inherent property of surface electromagnetic fields and its study has led to the discovery of phenomena such as unidirectional guided waves and photonic spin lattices. Previously, dispersion was ignored in spin-momentum locking, resulting in anomalies contradicting the apparent physical reality. Here, we formulate four dispersive spin-momentum equations, revealing in theory that transverse spin is locked with kinetic momentum. Moreover, in dispersive metal or magnetic materials spin-momentum locking obeys the left-hand screw rule. In addition to dispersion, structural features can affect substantially this locking. Remarkably, an extraordinary spin originating from coupling polarization ellipticities is uncovered that depends on the symmetry of the field modes. We further identify the properties of this spin-momentum locking with diverse photonic topological lattices by engineering their rotational symmetry akin to that in solid-state physics. The concept of spin-momentum locking based on photon flow properties translates easily to other classical wave fields.
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Affiliation(s)
- Peng Shi
- Nanophotonics Research Centre, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Shenzhen University, Shenzhen 518060, China
| | - Xinrui Lei
- Nanophotonics Research Centre, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Shenzhen University, Shenzhen 518060, China
| | - Qiang Zhang
- Nanophotonics Research Centre, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Shenzhen University, Shenzhen 518060, China
| | - Heng Li
- Nanophotonics Research Centre, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Shenzhen University, Shenzhen 518060, China
| | - Luping Du
- Nanophotonics Research Centre, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Shenzhen University, Shenzhen 518060, China
| | - Xiaocong Yuan
- Nanophotonics Research Centre, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Shenzhen University, Shenzhen 518060, China
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24
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Cheng J, Sha X, Zhang H, Chen Q, Qu G, Song Q, Yu S, Xiao S. Ultracompact Orbital Angular Momentum Sorter on a CMOS Chip. NANO LETTERS 2022; 22:3993-3999. [PMID: 35510871 DOI: 10.1021/acs.nanolett.2c00572] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
On-chip integrated orbital angular momentum (OAM) sorting is of great importance in tackling the severe challenge of exponential growth in data traffic. Despite the continuous success, current demultiplexing techniques either scarify efficiency dramatically or lose the compactness of a system. Here we experimentally demonstrate an ultracompact OAM sorter using TiO2 metasurfaces integrated onto a complementary metal-oxide-semiconductor (CMOS) camera. By utilizing the propagation phases, we transfer the unitary transformation theory in bulky systems into two TiO2 metasurfaces, responsible for the functions of log-polar transformation and fan-out beam copying and focusing as well as the functions of phase correction and Fourier transform. The flatform metasurface doublet enables one to integrate the OAM sorter onto a camera chip. Consequently, OAM beams with topological charges of m = -3 to 3 were separated by a CMOS camera with an average crosstalk of -6.43 dB. This approach shall shed light on next-generation OAM modes processing.
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Affiliation(s)
- Jiaping Cheng
- Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, P. R. China
| | - Xinbo Sha
- Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, P. R. China
| | - Hui Zhang
- Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, P. R. China
| | - Qinmiao Chen
- Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, P. R. China
| | - Geyang Qu
- Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, P. R. China
| | - Qinghai Song
- Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, P. R. China
| | - Shaohua Yu
- Pengcheng Laboratory, Shenzhen 518055, P. R. China
| | - Shumin Xiao
- Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, P. R. China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, Shanxi, P. R. China
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25
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Abstract
With the idea to find geometric formulations of particle physics we investigate the predictions of a three-dimensional generalization of the Sine-Gordon model, very close to the Skyrme model and to the Wu-Yang description of Dirac monopoles. With three rotational degrees of freedom of spatial Dreibeins, we formulate a Lagrangian and confront the predictions to electromagnetic phenomena. Stable solitonic excitations we compare with the lightest fundamental electric charges, electrons, and positrons. Two Goldstone bosons we relate to the properties of photons. These particles are characterized by three topological quantum numbers, which we compare to charge, spin, and photon numbers. Finally, we conjecture some ideas for further comparisons with experiments.
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26
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Abstract
Optical skyrmions have recently been constructed by tailoring vectorial near-field distributions through the interference of multiple surface plasmon polaritons, offering promising features for advanced information processing, transport and storage. Here, we provide experimental demonstration of electromagnetic skyrmions based on magnetic localized spoof plasmons (LSP) showing large topological robustness against continuous deformations, without stringent external interference conditions. By directly measuring the spatial profile of all three vectorial magnetic fields, we reveal multiple π-twist target skyrmion configurations mapped to multi-resonant near-equidistant LSP eigenmodes. The real-space skyrmion topology is robust against deformations of the meta-structure, demonstrating flexible skyrmionic textures for arbitrary shapes. The observed magnetic LSP skyrmions pave the way to ultra-compact and robust plasmonic devices, such as flexible sensors, wearable electronics and ultra-compact antennas.
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