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polarization modulation and Detection Based on Nonuniform Phase Gradient Metasurfaces

PLASMONICS 2025年 1-16页

作者： Pang, Kunwei Zhang, Wei Inst Appl Phys & Computat Math Natl Key Lab Computat Phys Beijing 100088 Peoples R China Beijing Computat Sci Res Ctr Beijing 100193 Peoples R China

Uniform phase gradient metasurfaces exhibit spatially varying platforms, resulting in deflecting a beam in a desired direction, while appropriately designed nonuniform phase gradient metasurfaces (NPGMs) may generate controllable multi-channel deflection. Using chiral symmetry of geometric phase and the interference between dual scattering channels, we propose the design of NPGMs made of identical nanorods (NRs) to realize anomalous reflection of arbitrary polarization under the incidence of arbitrary linear or elliptical polarization. In addition, we design NPGMs for the detection of the polarization state of the incidence by measuring the intensities of four reflected channels. The detection range of the state of polarization (SOP) of the incident beam can cover the entire Poincar & eacute;sphere. All the results based on Huygens theory agree well with those from finite-difference time-domain (FDTD) simulation. Our design of the metasurfaces based on the geometric phase has the characteristics of easy integration, multi-function and dispersionless, and provides general design guidance for metasurface polarization devices.

关键词： Metasurface Geometric phase polarization modulation Polarimeter

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polarization modulation and Optical Sensing Enabled by Nonradiative Modes in Dielectric Metasurfaces

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IEEE PHOTONICS TECHNOLOGY LETTERS 2024年第2期36卷 135-138页

作者： Li, Junjie Cheng, Yang Zeng, Dongwen Liu, Zhengqi Liu, Wei Liu, Guiqiang Jiangxi Normal Univ Coll Phys & Commun Elect Nanchang 330022 Jiangxi Peoples R China

All-dielectric metasurfaces exhibit lower ohmic losses than plasmonic metasurfaces. However, the dominant radiation losses still greatly hinder their applications and further development. Nonradiative modes such as bound states in continuum (BICs) and anapole modes have recently emerged as key research focuses. In this work, we theoretically propose an all-dielectric metasurface consisting of an array of regular octagons with nanopores to simultaneously realize anapole modes and BICs. By introducing symmetry breaking, two symmetry-protected BICs are transformed into quasi-BICs with ultra-high quality (Q)-factors of 26892 and 51874. The metasurface displays distinct polarization insensitivity of anapole mode and polarization dependence of quasi-BICs. Moreover, superior multi-mode and low-loss refractive index sensing performance is also realized with large sensitivities of 210, 191 and 241.7-nm/RIU and high figures of merit (FOMs) of 3500, 1910 and 69 RIU-1 in the wavelength range between 1200 and 1400-nm. These demonstrate that this all-dielectric metasurface has excellent potential in strong coupling regime, quasi-BICs polarization modulation, and high-sensitive refractive index sensing, etc.

关键词： Metasurfaces Nanopores Q-factor Optical sensors Refractive index Optical losses modulation Bound states in the continuum (BICs) anapole polarization modulation high Q-factors optical sensing

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Dual-color live-cell super-resolution fluorescence lifetime imaging via polarization modulation-based fluorescence emission difference

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OPTICS AND LASERS IN ENGINEERING 2025年 184卷

作者： Dong, Wanjie Huang, Yuran Tao, Wenli Xu, Liang Han, Yubing Hao, Xiang Kuang, Cuifang Liu, Xu Zhejiang Univ Coll Opt Sci & Engn State Key Lab Extreme Photon Hangzhou 310027 Peoples R China ZJU Hangzhou Global Sci & Technol Innovat Ctr Hangzhou 311100 Peoples R China Shanxi Univ Collaborat Innovat Ctr Extreme Opt Taiyuan 030006 Peoples R China

Fluorescence lifetime imaging microscopy (FLIM) has been proposed as an important technique for understanding the chemical microenvironment in cells and tissues, as it provides additional information compared to conventional fluorescence imaging. However, it is often hindered by limited spatial resolution and signal-to-noise ratio (SNR). In this study, we introduce a dual-color super-resolution FLIM method, termed Parallel Detection and Fluorescence Emission Difference (PDFED) FLIM. The integration of parallel detection with photon reassignment enhances photon efficiency, SNR, and resolution effectively. Additionally, differential imaging employing polarization modulation effectively reduces artifacts resulting from sample changes during live-cell imaging. PDFED-FLIM demonstrates enhancements in spatial resolution by approximately 1.6 times and peak signal-to-noise ratio (PSNR) by around 1.3 times. Furthermore, live-cell imaging showcases improved resolution and image quality, signifying the extensive potential of PDFED-FLIM in biomedical applications.

关键词： Fluorescence lifetime imaging microscopy Parallel detection polarization modulation Fluorescence emission difference microscopy

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Three-dimensional dipole orientation mapping with high temporal-spatial resolution using polarization modulation

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PhotoniX 2024年第1期5卷 512-531页

作者： Suyi Zhong Liang Qiao Xichuan Ge Xinzhu Xu Yunzhe Fu Shu Gao Karl Zhanghao Huiwen Hao Wenyi Wang Meiqi Li Peng Xi Department of Biomedical Engineering College of Future TechnologyPeking UniversityBeijing 100871China National Biomedical Imaging Center Peking UniversityBeijing 100871China Airy Technologies Co. Ltd.BeijingChina Institute of Molecular Medicine National Biomedical Imaging CenterCollege of Future TechnologyPeking UniversityBeijing 100871China Standard Imaging Company BeijingChina School of Life Sciences Peking UniversityBeijing 100871China

Fluorescence polarization microscopy is widely used in biology for molecular orientation ***,due to the limited temporal resolution of single-molecule orientation localization microscopy and the limited orientation dimension of polarization modulation techniques,achieving simultaneous high temporal-spatial resolution mapping of the three-dimensional(3D)orientation of fluorescent dipoles remains an outstanding ***,we present a super-resolution 3D orientation mapping(3DOM)microscope that resolves 3D orientation by extracting phase information of the six polarization modulation components in reciprocal space.3DOM achieves an azimuthal precision of 2°and a polar precision of 3°with spatial resolution of up to 128 nm in the *** validate that 3DOM not only reveals the heterogeneity of the milk fat globule membrane,but also elucidates the 3D structure of biological filaments,including the 3D spatial conformation ofλ-DNA and the structural disorder of actin ***,3DOM images the dipole dynamics of microtubules labeled with green fluorescent protein in live U2OS cells,reporting dynamic 3D orientation *** its easy integration into existing wide-field microscopes,we expect the 3DOM microscope to provide a multi-view versatile strategy for investigating molecular structure and dynamics in biological macromolecules across multiple spatial and temporal scales.

关键词： Fluorescence polarization microscopy Super-resolution imaging polarization modulation 3D orientation mapping

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Ship Contour Extraction from Polarimetric SAR Images Based on polarization modulation

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REMOTE SENSING 2024年第19期16卷 3669页

作者： Wu, Guoqing Wang, Shengbin Luo Liu, Yibin Wang, Ping Li, Yongzhen Natl Univ Def Technol Coll Elect Sci & Technol Changsha 410073 Peoples R China

Ship contour extraction is vital for extracting the geometric features of ships, providing comprehensive information essential for ship recognition. The main factors affecting the contour extraction performance are speckle noise and amplitude inhomogeneity, which can lead to over-segmentation and missed detection of ship edges. Polarimetric synthetic aperture radar (PolSAR) images contain rich target scattering information. Under different transmitting and receiving polarization, the amplitude and phase of pixels can be different, which provides the potential to meet the uniform requirement. This paper proposes a novel ship contour extraction framework from PolSAR images based on polarization modulation. Firstly, the image is partitioned into the foreground and background using a super-pixel unsupervised clustering approach. Subsequently, an optimization criterion for target amplitude modulation to achieve uniformity is designed. Finally, the ship's contour is extracted from the optimized image using an edge-detection operator and an adaptive edge extraction algorithm. Based on the contour, the geometric features of ships are extracted. Moreover, a PolSAR ship contour extraction dataset is established using Gaofen-3 PolSAR images, combined with expert knowledge and automatic identification system (AIS) data. With this dataset, we compare the accuracy of contour extraction and geometric features with state-of-the-art methods. The average errors of extracted length and width are reduced to 20.09 m and 8.96 m. The results demonstrate that the proposed method performs well in both accuracy and precision.

关键词： PolSAR ship contour extraction polarization modulation edge detection

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polarization modulation in Quantum-Dot Spin-VCSELs for Ultrafast Data Transmission

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IEEE JOURNAL OF QUANTUM ELECTRONICS 2023年第5期59卷 1页

作者： Tselios, Christos Georgiou, Panagiotis Politi, Christina Hurtado, Antonio Alexandropoulos, Dimitris Univ Peloponnese Dept Elect & Comp Engn Patras 22100 Greece Univ Patras Dept Mat Sci Rion 26504 Achaia Greece Univ Strathclyde Inst Photon Technol & Innovat Ctr Dept Phys Glasgow G1 1RD Scotland

Spin-Vertical Cavity Surface Emitting Lasers (spin-VCSELs) are undergoing increasing research effort for new paradigms in high-speed optical communications and photon-enabled computing. To date research in spin-VCSELs has mostly focused on Quantum-Well (QW) devices. However, novel Quantum-Dot (QD) spin-VCSELs, offer enhanced parameter controls permitting the effective, dynamical and ultrafast manip-ulation of their light emission's polarization. In the present contribution we investigate theoretically in detail the operation of QD spin-VCSELs subject to polarization modulation for their use as ultrafast light sources in optical communication systems. We reveal that QD spin-VCSELs outperform their QW counterparts in terms of modulation efficiency, yielding a nearly two-fold improvement. We also analyse the impact of key device parameters in QD spin-VCSELs (e.g. photon decay rate and intra-dot relaxation rate) on the large signal modulation perfor-mance with regard to simulated optical modulation amplitude and eye-diagram opening penalty. We show that in addition to exhibiting enhanced polarization modulation performance for data rates up to 250Gb/s, QD spin-VCSELs enable operation in dual (ground and excited state) emission thus allowing future exciting routes for multiplexing of information in computing and processing applications.

关键词： Ultrafast spin-lasers quantum-dot spin-VCSEL polarization modulation polarization dynamics

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polarization modulation for Wireless Communications Based on Metasurfaces

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ADVANCED FUNCTIONAL MATERIALS 2021年第36期31卷 2103379-2103379页

作者： Huang, Chen Xi Zhang, Jingjing Cheng, Qiang Cui, Tie Jun Southeast Univ Inst Electromagnet Space State Key Lab Millimeter Waves Nanning 210096 Peoples R China Pazhou Lab Guangzhou 510330 Peoples R China

As an alternative to conventional wireless communication techniques that use amplitude, frequency, and phase modulations, polarization modulation (PoM) provides an additional degree of freedom for the modulation of carrier waves and allows the realization of simple transceiver designs. PoM also enhances physical-layer security in wireless communication systems owing to its vector-attribute and direction-dependence features. In this study, a prototype of PoM wireless communications based on a digital coding metasurface that can dynamically control the polarization of electromagnetic waves in a certain frequency band is demonstrated. The binary digital signals can be encoded on the optical rotation states of the circularly polarized beams through the real-time control of the bias voltages applied on the metasurface and successfully decoded at the receiving end. Because the metasurface is separated from the emitting antenna, the design can simplify the setup for multichannel communications and provide more flexibility by setting the emitting antennas at different operating frequencies at any time.

关键词： polarization modulation programmable metasurfaces wireless communication

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Effects of polarization modulation Induced by Electro-Optic Modulators in Fiber-Based Setups

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IEEE PHOTONICS TECHNOLOGY LETTERS 2022年第3期34卷 185-188页

作者： Du-Burck, Frederic Manamanni, Karim Steshchenko, Tatiana Ramdane, Amine Chaouche Roncin, Vincent Univ Sorbonne Paris Nord UMR CNRS 7538 Lab Phys Lasers F-93430 Villetaneuse France

Using the Jones formalism, it is shown that electro-optic modulators used for phase modulation generate a modulation of the output polarization induced by the difference of phase modulation depth along the crystallographic axes of the modulator. We study two consequences of this polarization modulation in the fiber setups, limiting the performance of high sensitivity measurement devices. The first one is its partial conversion into a residual amplitude modulation (RAM) within any component presenting polarization dependent losses (PDL). The second one is a new effect that consists of the distortion of the signal detected at the output of a fiber cavity. The theoretical expressions of the detected signals are computed in each case.

关键词： modulation Random access memory Optical fiber polarization Phase modulation Optical fiber devices Frequency modulation polarization Electro-optic modulator fiber ring cavity polarization modulation residual amplitude modulation

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Rotating Permanent Magnet Antenna Array Based on Near-Field polarization modulation

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IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS 2022年第6期21卷 1193-1197页

作者： Sun, Faxiao Zhang, Feng Ma, Xiaoya Ji, Yicai Fang, Guangyou Chinese Acad Sci Aerosp Informat Res Inst Key Lab Electromagnet Radiat & Sensing Technol Beijing 100190 Peoples R China Univ Chinese Acad Sci Sch Elect Elect & Commun Engn Beijing 100049 Peoples R China

As a new type of low-frequency magnetic antenna, the rotating permanent magnet antenna (RPMA) has great application potential in underwater and underground communication. An RPMA array based on near-field polarization modulation is presented in this letter. The near-field polarization modulation is proposed because the RPMA can radiate circularly polarized magnetic fields in the direction of the rotation axis. Since the RPMA is intrinsically an electrically small antenna, it can only work in the near-field area where the field decays with the third power of the distance. The 1 x 2 array, which can enhance the field strength, is manufactured and tested. The measured results of the axial ratio and phase difference show that the proposed method is effective when the offset angle is not greater than 5.7 degrees. A communication experiment is also carried out, and the results show that the RPMA array can achieve a transmission rate of 2 bps.

关键词： Antenna arrays Magnetic domains Magnetic levitation Permanent magnets Permanent magnet motors Frequency measurement Phase modulation Circular polarization polarization modulation rotating permanent magnet antenna (RPMA) array

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Background suppression structured illumination microscopy based on polarization modulation

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OPTICS AND LASER TECHNOLOGY 2024年 177卷

作者： Zhu, Yukun Ji, Cheng Chen, Yunbo Hu, Huiqin He, Ning Zhang, Jinfeng Chen, Youhua Liu, Wenjie Kuang, Cuifang Zhejiang Univ Ningbo Inovat Ctr Ningbo 315100 Peoples R China Zhejiang Univ Coll Opt Sci & Engn Hangzhou 310000 Peoples R China Zhejiang Lab Res Ctr Intelligent Chips & Devices Hangzhou 311121 Peoples R China

We report a structured illumination microscopy (SIM) reconstruction method based on polarization modulation (PM), which can suppress background noise by utilizing the polarization-sensitivity properties of fluorescent dipoles. The proposed method employs a ferroelectric liquid crystal (FLC) spatial light modulator (SLM) to generate multidirectional interference patterns, and uses a combination of two liquid crystal variable phase retarders (LCVRs) and a quarter-wave plate (QWP) for flexible and rapid polarization modulation. The results of simulations and experiments demonstrate that the combination of SIM and PM effectively suppresses background noise in SIM with a slight improvement in resolution. This technique also solves the problem of structural distortion that occasionally exists in SIM and improves the accuracy of the reconstruction.

关键词： polarization modulation Background suppression Multidirectional integration Fluorescent dipoles Structured illumination microscopy

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