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Sun Y, Cai B, Yang L, Wu L, Cheng Y, Luo H, Chen F, Li X. High-Gain Dual-Polarization Microstrip Antenna Based on Transmission Focusing Metasurface. MATERIALS (BASEL, SWITZERLAND) 2024; 17:3730. [PMID: 39124394 PMCID: PMC11313525 DOI: 10.3390/ma17153730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Revised: 06/08/2024] [Accepted: 07/24/2024] [Indexed: 08/12/2024]
Abstract
In this paper, a single-feed microstrip antenna (MA) equipped with a transmission-mode focusing metasurface (MS) is proposed to achieve dual-polarization capabilities and superior high-gain radiation performance. The original-feed MA comprises two distinct layers of coaxial-fed tangential patches, enabling it to emit a circular polarization (CP) wave with a gain of 3.5 dBic at 5.6 GHz and linear polarization (LP) radiation with a gain of 4 dBi at 13.7 GHz. To improve the performance of the single-feed MA, a dual-polarization transmission focusing MS is proposed and numerically substantiated. By positioning the originally designed MA at the focal point of the MS, we create a transmission-mode MS antenna system capable of achieving CP and LP radiations with the significantly higher gains of 12.9 dBic and 14.8 dBi at 5.6 GHz and 13.7 GHz, respectively. Measurements conducted on the fabricated dual-polarization focusing MS antenna closely align with the simulation results, validating the effectiveness of our approach. This work underscores the significant potential of dual-polarization high-speed data systems and offers a practical solution for enhancing antenna gains in contemporary wireless communication systems.
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Affiliation(s)
- Yibo Sun
- School of Information Science and Engineering, Engineering Research Center for Metallurgical Automation and Detecting Technology Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081, China; (Y.S.); (B.C.); (H.L.); (F.C.)
| | - Bin Cai
- School of Information Science and Engineering, Engineering Research Center for Metallurgical Automation and Detecting Technology Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081, China; (Y.S.); (B.C.); (H.L.); (F.C.)
| | - Lingling Yang
- School of Electronic Engineering, Wuhan Open University, Wuhan 430205, China;
| | - Ling Wu
- School of Physics and Electronic Information Engineering, Hubei Engineering University, Xiaogan 432000, China;
| | - Yongzhi Cheng
- School of Information Science and Engineering, Engineering Research Center for Metallurgical Automation and Detecting Technology Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081, China; (Y.S.); (B.C.); (H.L.); (F.C.)
- Key Laboratory of High Temperature Electromagnetic Materials and Structure of MOE, Wuhan University of Science and Technology, Wuhan 430081, China
| | - Hui Luo
- School of Information Science and Engineering, Engineering Research Center for Metallurgical Automation and Detecting Technology Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081, China; (Y.S.); (B.C.); (H.L.); (F.C.)
- Key Laboratory of High Temperature Electromagnetic Materials and Structure of MOE, Wuhan University of Science and Technology, Wuhan 430081, China
| | - Fu Chen
- School of Information Science and Engineering, Engineering Research Center for Metallurgical Automation and Detecting Technology Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081, China; (Y.S.); (B.C.); (H.L.); (F.C.)
- Key Laboratory of High Temperature Electromagnetic Materials and Structure of MOE, Wuhan University of Science and Technology, Wuhan 430081, China
| | - Xiangcheng Li
- School of Physics and Electronic Information Engineering, Hubei Engineering University, Xiaogan 432000, China;
- Key Laboratory of High Temperature Electromagnetic Materials and Structure of MOE, Wuhan University of Science and Technology, Wuhan 430081, China
- The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, China
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Wang L, Liu N, Wu C, Chen G. Dynamical encircling of multiple exceptional points in anti-PT symmetry system. OPTICS EXPRESS 2024; 32:21616-21628. [PMID: 38859511 DOI: 10.1364/oe.524678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Accepted: 05/21/2024] [Indexed: 06/12/2024]
Abstract
Exceptional points (EPs) in non-Hermitian systems have turned out to be at the origin of many intriguing effects with no counterparts in Hermitian cases. A typically interesting behavior is the chiral mode switching by dynamically winding the EP. Most encircling protocols focus on the two-state or parity-time (PT) symmetry systems. Here, we propose and investigate the dynamical encircling of multiple EPs in an anti-PT-symmetric system, which is constructed based on a one-dimensional lattice with staggered lossy modulation. We reveal that dynamically encircling the multiple EPs results in the chiral dynamics via multiple non-Hermiticity-induced nonadiabatic transitions, where the output state is always on the lowest-loss energy sheet. Compared with the PT-symmetric systems that require complicated variation of the gain/loss rate or on-site potentials, our system only requires modulations of the couplings which can be readily realized in various experimental platforms. Our scheme provides a route to study non-Hermitian physics by engineering the EPs and implement novel photonic devices with unconventional functions.
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Hu H, Fu X, Qi J, Zhang S, Wu Q, Lu Y, Chen Z, Chen J, Yu X, Wang X, Sun Q, Xu J. Omni-polarized Faraday isolator based on non-Hermitian Faraday system. OPTICS EXPRESS 2024; 32:18594-18604. [PMID: 38859012 DOI: 10.1364/oe.522109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 04/22/2024] [Indexed: 06/12/2024]
Abstract
Non-Hermitian systems have recently attracted significant attention in photonics due to the realization that the interplay between gain and loss can lead to entirely new and unexpected features. Here, we propose and demonstrate a non-Hermitian Faraday system capable of non-reciprocal omni-polarizer action at the exceptional point. Notably, both forward and backward propagating light with arbitrary polarization converge to the same polarization state. Leveraging the robustness and non-reciprocity of the non-Hermitian Faraday system, we realize an omni-polarized Faraday isolator that can effectively isolate any polarized light without the need for a polarizer at the incident port of backward propagation. Remarkably, under the given parameter configuration, the isolator achieves a maximum isolation ratio of approximately 100 dB and a minimum isolation ratio of around 45 dB for various polarized light, accompanied by near-zero insertion loss. Furthermore, our research reveals the remarkable tolerance of the non-Hermitian Faraday isolator to nonlinear effects. This unique characteristic allows us to harness nonlinear effects to achieve various optical functions, all while maintaining excellent isolation performance. The proposed non-Hermitian Faraday system paves the way for the realization of magnetically or optically switchable non-reciprocal devices.
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Shu X, Zhong Q, Hong K, You O, Wang J, Hu G, Alù A, Zhang S, Christodoulides DN, Chen L. Chiral transmission by an open evolution trajectory in a non-Hermitian system. LIGHT, SCIENCE & APPLICATIONS 2024; 13:65. [PMID: 38438358 PMCID: PMC10912664 DOI: 10.1038/s41377-024-01409-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 01/28/2024] [Accepted: 02/12/2024] [Indexed: 03/06/2024]
Abstract
Exceptional points (EPs), at which two or more eigenvalues and eigenstates of a resonant system coalesce, are associated with non-Hermitian Hamiltonians with gain and/or loss elements. Dynamic encircling of EPs has received significant interest in recent years, as it has been shown to lead to highly nontrivial phenomena, such as chiral transmission in which the final state of the system depends on the encircling handedness. Previously, chiral transmission for a pair of eigenmodes has been realized by establishing a closed dynamical trajectory in parity-time- (PT-) or anti-PT-symmetric systems. Although chiral transmission of symmetry-broken modes, more accessible in practical photonic integrated circuits, has been realized by establishing a closed trajectory encircling EPs in anti-PT-symmetric systems, the demonstrated transmission efficiency is very low due to path-dependent losses. Here, we demonstrate chiral dynamics in a coupled waveguide system that does not require a closed trajectory. Specifically, we explore an open trajectory linking two infinite points having the same asymptotic eigenmodes (not modes in PT- and anti-PT-symmetric systems), demonstrating that this platform enables high-efficiency chiral transmission, with each eigenmode localized in a single waveguide. This concept is experimentally implemented in a coupled silicon waveguide system at telecommunication wavelengths. Our work provides a new evolution strategy for chiral dynamics with superior performance, laying the foundation for the development of practical chiral-transmission devices.
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Affiliation(s)
- Xiaoqian Shu
- Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
- Zhejiang Lab, Hangzhou, 311121, China
| | - Qi Zhong
- CREOL, College of Optics and Photonics, University of Central Florida, Orlando, Florida, 32816, USA
| | - Kai Hong
- Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Oubo You
- Department of Physics, The University of Hong Kong, Hong Kong, China
| | - Jian Wang
- Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Guangwei Hu
- School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Andrea Alù
- Photonics Initiative, Advanced Science Research Center, City University of New York, New York, NY, 10031, USA
| | - Shuang Zhang
- Department of Physics, The University of Hong Kong, Hong Kong, China
| | | | - Lin Chen
- Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China.
- Shenzhen Huazhong University of Science and Technology Research Institute, Shenzhen, 518063, China.
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He T, Zhang Z, Zhu J, Shi Y, Li Z, Wei H, Wei Z, Li Y, Wang Z, Qiu CW, Cheng X. Scattering exceptional point in the visible. LIGHT, SCIENCE & APPLICATIONS 2023; 12:229. [PMID: 37714831 PMCID: PMC10504253 DOI: 10.1038/s41377-023-01282-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 08/28/2023] [Accepted: 09/04/2023] [Indexed: 09/17/2023]
Abstract
Exceptional point (EP) is a special degeneracy of non-Hermitian systems. One-dimensional transmission systems operating at EPs are widely studied and applied to chiral conversion and sensing. Lately, two-dimensional systems at EPs have been exploited for their exotic scattering features, yet so far been limited to only the non-visible waveband. Here, we report a universal paradigm for achieving a high-efficiency EP in the visible by leveraging interlayer loss to accurately control the interplay between the lossy structure and scattering lightwaves. A bilayer framework is demonstrated to reflect back the incident light from the left side ( | r-1 | >0.999) and absorb the incident light from the right side ( | r+1 | < 10-4). As a proof of concept, a bilayer metasurface is demonstrated to reflect and absorb the incident light with experimental efficiencies of 88% and 85%, respectively, at 532 nm. Our results open the way for a new class of nanoscale devices and power up new opportunities for EP physics.
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Grants
- 61925504, 62192770, 61621001, 62205246, 62020106009, 6201101335, 62205249, 62192772, 62192771 National Natural Science Foundation of China (National Science Foundation of China)
- Shanghai Pilot Program for Basic Research, Science and Technology Commission of Shanghai Municipality (17JC1400800, 20JC1414600, 21JC1406100) the “Shu Guang” project supported by Shanghai Municipal Education Commission and Shanghai Education (17SG22) Shanghai Municipal Science and Technology Major Project (2021SHZDZX0100) Special Development Funds for Major Projects of Shanghai Zhangjiang National Independent Innovation Demonstration Zone (Grant No. ZJ2021-ZD-008) The Fundamental Research Funds for the Central Universities
- Project funded by China Postdoctoral Science Foundation (2022M712401)
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Affiliation(s)
- Tao He
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai, 200092, China
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, 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
- Shanghai Professional Technical Service Platform for Full-Spectrum and High-Performance Optical Thin Film Devices and Applications, Shanghai, 200092, China
- Department of Electronic Science and Technology, Tongji University, Shanghai, 201804, China
| | - Zhanyi Zhang
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai, 200092, China
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, 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
- Shanghai Professional Technical Service Platform for Full-Spectrum and High-Performance Optical Thin Film Devices and Applications, Shanghai, 200092, China
| | - Jingyuan Zhu
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai, 200092, China
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, 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
- Shanghai Professional Technical Service Platform for Full-Spectrum and High-Performance Optical Thin Film Devices and Applications, Shanghai, 200092, China
| | - Yuzhi Shi
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai, 200092, China
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, 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
- Shanghai Professional Technical Service Platform for Full-Spectrum and High-Performance Optical Thin Film Devices and Applications, Shanghai, 200092, China
| | - Zhipeng Li
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Heng Wei
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Zeyong Wei
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai, 200092, China
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, 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
- Shanghai Professional Technical Service Platform for Full-Spectrum and High-Performance Optical Thin Film Devices and Applications, Shanghai, 200092, China
| | - Yong Li
- Institute of Acoustics, School of Physics Science and Engineering, Tongji University, Shanghai, 20092, China
| | - Zhanshan Wang
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai, 200092, China
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, 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
- Shanghai Professional Technical Service Platform for Full-Spectrum and High-Performance Optical Thin Film Devices and Applications, Shanghai, 200092, China
| | - Cheng-Wei Qiu
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, 117583, Singapore.
| | - Xinbin Cheng
- MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai, 200092, China.
- Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, 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.
- Shanghai Professional Technical Service Platform for Full-Spectrum and High-Performance Optical Thin Film Devices and Applications, Shanghai, 200092, China.
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Hong K, Chen L. Mie scatterers bring a resonator to an exceptional point. LIGHT, SCIENCE & APPLICATIONS 2023; 12:216. [PMID: 37666827 PMCID: PMC10477206 DOI: 10.1038/s41377-023-01258-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/06/2023]
Abstract
Exceptional points have given rise to many intriguing optical phenomena that are of fundamental importance for a variety of breakthrough technologies. The pre-defined Mie scatterers can bring a resonator to an exceptional point, and result in enhanced quality factor through coherently suppressing the backward scattering.
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Affiliation(s)
- Kai Hong
- Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Lin Chen
- Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China.
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7
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Li Z, Li C, Xu G, Chen W, Xiong Z, Jing H, Ho JS, Qiu CW. Synergetic positivity of loss and noise in nonlinear non-Hermitian resonators. SCIENCE ADVANCES 2023; 9:eadi0562. [PMID: 37406112 DOI: 10.1126/sciadv.adi0562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 06/01/2023] [Indexed: 07/07/2023]
Abstract
Loss and noise are usually undesirable in electronics and optics, which are generally mitigated by separate ways in the cost of bulkiness and complexity. Recent studies of non-Hermitian systems have shown a positive role of loss in various loss-induced counterintuitive phenomena, while noise still remains a fundamental challenge in non-Hermitian systems particularly for sensing and lasing. Here, we simultaneously reverse the detrimental loss and noise and reveal their coordinated positive role in nonlinear non-Hermitian resonators. This synergetic effect leads to the amplified spectrum intensity with suppressed spectrum fluctuations after adding both loss and noise. We reveal the underlying mechanism of nonlinearity-induced bistability engineered by loss in the non-Hermitian resonators and noise-loss enhanced coherence of eigenfrequency hopping driven by temporal modulation of detuning. Our findings enrich counterintuitive non-Hermitian physics and lead to a general recipe to overcome loss and noise from electronics to photonics with applications from sensing to communication.
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Affiliation(s)
- Zhipeng Li
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
| | - Chenhui Li
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
| | - Guoqiang Xu
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
| | - Weijin Chen
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
| | - Ze Xiong
- Wireless and Smart Bioelectronics Lab, School of Biomedical Engineering, ShanghaiTech University, Shanghai 201210, China
| | - Hui Jing
- Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, Department of Physics and Synergetic Innovation Center for Quantum Effects and Applications, Hunan Normal University, Changsha 410081, China
| | - John S Ho
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
| | - Cheng-Wei Qiu
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
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Li A, Wei H, Cotrufo M, Chen W, Mann S, Ni X, Xu B, Chen J, Wang J, Fan S, Qiu CW, Alù A, Chen L. Exceptional points and non-Hermitian photonics at the nanoscale. NATURE NANOTECHNOLOGY 2023; 18:706-720. [PMID: 37386141 DOI: 10.1038/s41565-023-01408-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 04/25/2023] [Indexed: 07/01/2023]
Abstract
Exceptional points (EPs) arising in non-Hermitian systems have led to a variety of intriguing wave phenomena, and have been attracting increased interest in various physical platforms. In this Review, we highlight the latest fundamental advances in the context of EPs in various nanoscale systems, and overview the theoretical progress related to EPs, including higher-order EPs, bulk Fermi arcs and Weyl exceptional rings. We peek into EP-associated emerging technologies, in particular focusing on the influence of noise for sensing near EPs, improving the efficiency in asymmetric transmission based on EPs, optical isolators in nonlinear EP systems and novel concepts to implement EPs in topological photonics. We also discuss the constraints and limitations of the applications relying on EPs, and offer parting thoughts about promising ways to tackle them for advanced nanophotonic applications.
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Affiliation(s)
- Aodong Li
- Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, China
| | - Heng Wei
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
| | - Michele Cotrufo
- Photonics Initiative, Advanced Science Research Center, City University of New York, New York, NY, USA
| | - Weijin Chen
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
| | - Sander Mann
- Photonics Initiative, Advanced Science Research Center, City University of New York, New York, NY, USA
| | - Xiang Ni
- Photonics Initiative, Advanced Science Research Center, City University of New York, New York, NY, USA
| | - Bingcong Xu
- Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, China
| | - Jianfeng Chen
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
| | - Jian Wang
- Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, China
| | - Shanhui Fan
- Department of Electrical Engineering, Ginzton Laboratory, Stanford University, Stanford, CA, USA
- Department of Applied Physics, Stanford University, Stanford, CA, USA
| | - Cheng-Wei Qiu
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore.
| | - Andrea Alù
- Photonics Initiative, Advanced Science Research Center, City University of New York, New York, NY, USA.
- Physics Program, Graduate Center, City University of New York, New York, NY, USA.
| | - Lin Chen
- Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, China.
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing, China.
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