Article
Chemistry, Multidisciplinary
Shahab Razavi, Yiping Zhao
Summary: This study demonstrates that a hybridized plasmonic mode in a compound nanohole structure can be described as a quasi-dipole oscillator. By introducing two nanorods into a nanohole, these two quasi-dipoles can couple and hybridize, resulting in additional transmission peaks. The intensities and separations of these peaks can be controlled by adjusting the incident polarization and modifying the nanorod length. This concept can be extended to predict the behavior of more complex compound configurations, allowing for precise engineering of transmission peaks.
Article
Chemistry, Multidisciplinary
Yun-Cheng Ku, Jiunn-Woei Liaw, Szu-Yao Mao, Mao-Kuen Kuo
Summary: Theoretical study on the transition of a helical surface plasmon polariton (SPP) from a circular nanohole in a thick metal film to a spiral SPP outward propagating at the film's interface shows that the propagation length of mode-1 SPP is significantly longer than other modes in a specific frequency band, depending on the nanohole size. Numerical results demonstrate that most of the energy flux fanning out at the outlet as a dipole radiation after a helical SPP tunnels through a nanohole.
Article
Nanoscience & Nanotechnology
Dongda Wu, Yi Wang, Yujun Liu, Junqiao La, Shijia He, Fanzhou Lv, Wenxin Wang
Summary: The interplay between light and matter at the nanoscale can be enhanced by Bloch surface plasmon polariton (Bloch-SPP) on the plasmonic lattice. An Ag nanohole array arranged in a hexagonal formation acted as an optical cavity to achieve directional and polarized amplified spontaneous emission (ASE) of R6G molecules. A 100-fold enhancement of ASE was observed at a 15-degree emission angle under TM polarization when the pump power density exceeded a threshold of 198 W/cm2 based on degenerated high state density modes. Additionally, the Bloch-SPP modes modulated a specific polarization dependence of ASE, with the degree of polarization increasing from 1.3 to 2.1 when the pump power density exceeded the ASE threshold. This work elucidates the interaction between gain media and plasmonic systems, providing a foundation for the design of plasmonic devices.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Physics, Applied
Yanfeng Wang, Zhengjun Zhang, Yiping Zhao
Summary: This study investigates the effect of moving the nanorod from the center to the edge of the nanohole, finding that breaking geometric symmetry can tune the resonant wavelength redshift of extraordinary optical transmission. Connecting the nanorod to the nanohole and increasing lattice period significantly redshifts the EOT mode, suitable for compact integrated optical device design.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Engineering, Electrical & Electronic
Yanfeng Wang, Inyoung Choi, Kaiyuan Zhang, Yanjun Yang, Shen Ao, Xiaotian Xue, Wangyang Fu, Zhengjun Zhang, Yiping Zhao
Summary: The large-area silver nanograting on nanohole structures prepared using nanosphere lithography and oblique angle deposition shows excellent electrical conductance and optical transmission, surpassing previously reported metal nanohole networks or transparent metallic films.
ACS APPLIED ELECTRONIC MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Shadman Shahid, Shahed-E- Zumrat, Muhammad Anisuzzaman Talukder
Summary: Plasmonic lasers have the potential for cutting-edge applications but face challenges such as high losses in metals and lack of spatial coherence. This study proposes a novel design using merged lattice metal nanohole arrays and a one-dimensional photonic crystal to achieve dual-mode lasing, offering intense laser output with low thresholds and highly directional far-field patterns.
NANOSCALE ADVANCES
(2022)
Article
Engineering, Electrical & Electronic
Jingfu Ye, Yan Li, Shiliang Qu
Summary: The study introduces a quarter-ring-shaped phase-gradient metasurface (QR-PGM) that sorts propagating waves into separate waveguide channels based on their orbital angular momentum states, showing high focusing efficiency and wide wavelength range. This compact and efficient structure can be easily integrated with other on-chip devices, providing new possibilities for high-capacity optical communication systems.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Nanoscience & Nanotechnology
Kevin T. Crampton, Alan G. Joly, Patrick Z. El-Khoury
Summary: The research demonstrates control over the spatial and temporal properties of surface plasmon polaritons (SPPs) launched from nanohole arrays in silver. The characteristics of the optical grating can be tuned through various nanohole array parameters, and temporal interference of SPPs with different central wavelengths can be achieved using multiperiodic arrays (MPAs).
Article
Nanoscience & Nanotechnology
Kevin T. Crampton, Alan G. Joly, Patrick Z. El-Khoury
Summary: The study demonstrates control over the spatial and temporal properties of surface plasmon polaritons (SPPs) launched from nanohole arrays in silver, showing that SPPs launched from multiple arrays can interfere at defined spatial positions to form an all-SPP periodic nano-optical grating that evolves as the SPPs propagate. The spatio-temporal characteristics of the optical grating can be tuned through various nanohole array parameters, and the temporal interference of SPPs with different central wavelengths can be tailored through multiperiodic arrays (MPAs) consisting of arrays with different pitches placed adjacent to one another. Temporal interference serves as an encoded signal, where frequency components can be controlled by array properties.
Article
Engineering, Electrical & Electronic
Hongxin Zhao, Jinlun Li, Qiuyi Zhang, Shunli Li, Xiaoxing Yin
Summary: This study presents a spoof surface plasmon polariton (SSPP) antenna with dual-band endfire gain and small frequency ratio (FR). The antenna uses an asymmetric structure to support two independent surface waves with different nonlinear phase constants, achieving dual-band endfire gain and endfire radiation null.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Chemistry, Analytical
Kang Yang, Meiying Li
Summary: In this study, it is theoretically investigated that the sensitivity of a hexagonal Au nanohole array sensor can be improved by 80% and 150% for bulk sensitivity and surface sensitivity, respectively, by simply increasing the incident angle from 0° to 40°. This finding is of great significance for enhancing and applying the performance of surface plasmon resonance sensors.
Article
Chemistry, Physical
Hoang Mai Luong, Minh Thien Pham, Tho Duc Nguyen, Yiping Zhao
Summary: The magneto-chiroptical properties of Ag/Co composite chiral nanohole arrays (CCNAs) were investigated in this study. It was found that the intrinsic circular dichroism of CCNA samples can be enhanced by surface plasmon resonance when Ag is a major component, while the Co component allows for magnetic tuning circular dichroism. Samples with high Ag concentration exhibited sharper and stronger magnetic circular dichroism, indicating the potential for large-scale active chiroptical metasurfaces.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Crystallography
Hassanein Shaban, Adel Shaaban, Marwa S. Salem, Lotfy Rabeh Gomaa, Mohamed Medhat, Yi-Chun Du
Summary: This study discusses the feasibility of using a thermotropic liquid crystal (TLC) material to fabricate a prism for a Kretschmann-based surface plasmon sensor, which can be thermally tuned to match the surface plasmon modes' excitation requirements. The TLC material has a stable thermal control and its refractive index changes linearly with temperatures in the visible region, allowing for a linear response to refractive index changes in the proposed surface plasmon sensor design.
Article
Optics
Jingjing Hong, Xingping Zhou, Rui Zhuang, Wei Peng, Jiawei Liu, Aiping Liu, Qin Wang
Summary: A stable and manipulatable nanoparticle trapping method called Counter-Surface Plasmon Polariton Lens (CSPPL) is proposed in this paper. By adjusting the incident angle and phase difference, the optical potential depth and center position on CSPPL can be accurately controlled. This study promotes the development of integrated optical tweezers.
CHINESE OPTICS LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Satya R. Kachiraju, Ivan Nekrashevich, Imtiaz Ahmad, Hira Farooq, Long Chang, Sangsik Kim, Myoung-Hwan Kim
Summary: This paper proposes subwavelength-scale resonant nanocavity arrays that enhance the absorption spectrum of mid-infrared light through the excitation of coupled surface plasmon-phonon polaritons. The structure supports angle-insensitive and frequency-tunable absorption, which can benefit various mid-infrared applications.
Article
Nanoscience & Nanotechnology
Nan Deng, Hua Long, Kun Wang, Xiaobo Han, Bing Wang, Kai Wang, Peixiang Lu
Summary: In this study, the optical anisotropy of tungsten disulfide (WS2) flakes was characterized with scattering-type scanning near-field optical microscopy. The use of an Au substrate enhanced the contrast of the near-field fringes. The refractive indices of WS2 were determined through near-field imaging and theoretical calculations, and a high birefringence value was observed. This work provides experimental evidence for the potential application of WS2 in optoelectronic integrated circuits in the visible region.
Article
Chemistry, Multidisciplinary
Zhenming Wang, Jianxun Liu, Jiawei Wang, Zongjun Ma, Delai Kong, Shouzhen Jiang, Dan Luo, Yan Jun Liu
Summary: This paper presents a cost-effective, large-sized, and highly reproducible SERS substrate prepared by nanosphere lithography technique. By manipulating the geometry of the Ag metasurface deposited on the substrate and coating a thin layer of graphene oxide, high enhancement factor and low detection limit of SERS performance have been achieved. Experimental results demonstrate the potential application value of this method for trace detection in fields like food safety control and environmental monitoring.
Review
Chemistry, Analytical
Xiyun Zhan, Yanjun Liu, Kun-Lin Yang, Dan Luo
Summary: This paper provides an overview of the latest research on liquid crystal (LC) sensors in the biochemical field. It discusses the basic properties of LC materials, the detection mechanisms of LC sensors, and different platforms for LC sensors. Various analytes detected by LCs are mentioned, along with a machine-learning-assisted LC sensing platform.
Article
Nanoscience & Nanotechnology
Yang Chen, Shuhang Qian, Kai Wang, Xiangyuan Xing, Andrew Wee, Kian Ping Loh, Bing Wang, Dong Wu, Jiaru Chu, Andrea Alu, Peixiang Lu, Cheng-Wei Qiu
Summary: Valleytronics, a promising technology for energy-efficient signal transport on chip, faces challenges in achieving high-fidelity, high-directionality, and room-temperature valley transport. In this study, a nanophotonic circuit is demonstrated to unidirectionally route valley indices using the chirality of photons, with 98% valley fidelity and a circulation directionality of 0.44 +/- 0.04 at room temperature. This research opens up possibilities for large-scale valleytronic networks and hybrid spin-valley-photon ecosystems at the nanoscale.
NATURE NANOTECHNOLOGY
(2022)
Article
Optics
Shan Li, Shaolin Ke, Bing Wang, Peixiang Lu
Summary: This study demonstrates stable Dirac points in low dimensions by utilizing non-Hermiticity in an optical lattice. The stability of Dirac points is maintained even with dissipation variations, and they can develop into nodal rings in two dimensions. The research opens up possibilities for controlling the flow of light to aid dissipation while maintaining high stability of energy.
Article
Optics
Lingzhi Zheng, Bing Wang, Chengzhi Qin, Lange Zhao, Shuyue Chen, Weiwei Liu, Peixiang Lu
Summary: A waveguide coupler capable of both phase and intensity modulation is proposed to create a non-Hermitian Su-Schrieffer-Heeger lattice in the frequency dimension. The manipulation of on-site potential and anisotropic coupling of supermodes in waveguides is achieved by varying the modulation period and phase. Additionally, an artificial electric field associated with the modulation phase is introduced. The study demonstrates Zener tunneling in the non-Hermitian system, showcasing irreversible unidirectional conversion between odd and even supermodes.
Article
Optics
Wenhui Yu, Xiang LI, Bing Wang, Junle Qu, Liwei Liu
Summary: Optical diffraction tomography (ODT) is a high-resolution imaging technique that allows imaging of the endogenous structure of matter. This article presents the theoretical basis and experimental considerations for ODT of second-order nonlinear structures in weak scattering media. The proposed method shows promising applications in nonlinear microscopy.
Article
Multidisciplinary Sciences
Shulin Wang, Chengzhi Qin, Weiwei Liu, Bing Wang, Feng Zhou, Han Ye, Lange Zhao, Jianji Dong, Xinliang Zhang, Stefano Longhi, Peixiang Lu
Summary: This study demonstrates higher-order dynamic localization of photons in a synthetic temporal mesh lattice and discusses the idea of tunable temporal cloaking by combining different-order localizations.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Zhenming Wang, Thomas Raistrick, Aidan Street, Matthew Reynolds, Yanjun Liu, Helen F. Gleeson
Summary: This study demonstrates the direct observation of biaxial order in an auxetic liquid crystal elastomer (LCE) under strain. The findings provide important insights into the mechanism of the auxetic response in LCEs and suggest that biaxial order is responsible for the negative Poisson's ratio exhibited by these materials.
Article
Optics
Mengjia Cen, Jiawei Wang, Jianxun Liu, Ye Li, Wenfeng Cai, Delai Kong, Dan Luo, Tun Cao, Yan Jun Liu
Summary: This study proposes a unique type of SLRs excited in suspended, self-aligned symmetric double-layer gratings with index-matched environment. The self-aligned double-layer gratings are fabricated using a single-step electron beam lithography and exhibit high-quality factors due to interference effects.
Article
Optics
He Huang, Yaoshuai Li, Chengzhi Qin, Wenwan Li, Lange Zhao, Chen Liu, Bing Wang, Chi Zhang, Peixiang Lu
Summary: In this study, the spectral self-imaging effect for a frequency comb is demonstrated using a four-wave mixing time lens. The time lens is created by applying a temporal quadratic phase modulation to the input signal pulses, which results in a frequency comb in the Fourier spectrum. The modulation is achieved by a Gaussian pump pulse in an external single-mode fiber. When both the signal and pump pulses are injected into a highly nonlinear fiber, four-wave mixing Bragg scattering occurs, leading to periodic revivals of the input frequency comb as the pump pulse propagates periodically. The study also reveals the impact of the envelope width of input pulses on the output spectrum width.
Article
Chemistry, Physical
Fengyuan Lin, Jinzhi Cui, Zhihong Zhang, Zhipeng Wei, Xiaobing Hou, Bingheng Meng, Yanjun Liu, Jilong Tang, Kexue Li, Lei Liao, Qun Hao
Summary: A high-performance GaAs nanowire photodetector was fabricated by modifying the surface defects with Au nanoparticles. Plasmons and Schottky barriers were introduced to enhance light absorption and carrier separation. The modified photodetectors showed reduced dark current and increased photocurrent and responsivity. The improvement in performance was analyzed using the energy band theory model. This work proposes a new method to enhance the performance of GaAs nanowire photodetectors.
Article
Multidisciplinary Sciences
Shulin Wang, Chengzhi Qin, Lange Zhao, Han Ye, Stefano Longhi, Peixiang Lu, Bing Wang
Summary: This paper introduces a new class of reconfigurable linear optics circuits harnessing Floquet LZT, which has versatile applications in temporal beam control, signal processing, quantum simulations, and information processing.
Article
Chemistry, Analytical
Zixuan Wu, Jianxun Liu, Zhenming Wang, Lei Chen, Yiwei Xu, Zongjun Ma, Delai Kong, Dan Luo, Yan Jun Liu
Summary: We demonstrated a low-cost, highly sensitive hybrid Ag-Cu substrate with enhanced absorption for the excitation laser beam via the nanosphere lithography technique. The substrate consists of a Cu nanoarray covered with Ag nanoparticles, resulting in optimized absorption for the laser beam. Raman enhancement is achieved by incorporating plasmonic hotspots formed by dense Ag nanoparticles. The hybrid Ag-Cu SERS substrates exhibit a highly sensitive and reproducible SERS activity, with potential applications in biosensors, environmental monitoring, and food safety.
Article
Optics
Shan Li, Shulin Wang, Shuyue Chen, Yanting Wu, Shaolin Ke, Bing Wang, Peixiang Lu
Summary: This study proposes a mechanism to achieve real energy spectra via Hermitian subspace in non-Hermitian systems, illustrated by a system composed of two identical Su-Schrieffer-Heeger chains. By tuning the coupling strength, both subsystems experience topological phase transition, allowing exploration of Hermitian and non-Hermitian topological edge modes simultaneously. The proposed model can be implemented in evanescently coupled optical waveguide arrays and extended to other tight-binding systems.
