Article
Nanoscience & Nanotechnology
Xuemei Dai, Fengliang Dong, Kun Zhang, Dingpeng Liao, Sheng Li, Zhengguo Shang, Yi Zhou, Gaofeng Liang, Zhihai Zhang, Zhongquan Wen, Gang Chen, Luru Dai, Weiguo Chu
Summary: In this paper, a holographic approach for achieving multiwavelength achromatic subwavelength super-resolution focusing is proposed, and a high-numerical-aperture achromatic super-resolution metalens is demonstrated at five different wavelengths. This method shows potential value in super-resolution related applications.
Article
Physics, Multidisciplinary
Zhixiang Wu, Yiyang Zou, Xinyu Li, Hu Deng, Liang Xiong, Quancheng Liu, Liping Shang
Summary: Lenses with sub-diffraction focusing are widely used in advanced optical imaging and microscopy. However, oblique incidence light can cause aberrations for high-NA metalenses. In this study, a high-NA (0.97) metalens design approach is demonstrated to provide sub-diffraction focusing for oblique incidence and broadband operation. The metalens is capable of sub-diffraction focusing over the wavelength range 600-750 nm and is ultra-thin and easy to integrate.
Article
Optics
Xinjian Lu, Yinghui Guo, Mingbo Pu, Yaxin Zhang, Zhu Li, Xiong Li, Xiaoliang Ma, Xiangang Luo
Summary: In this article, a single-layer broadband achromatic metasurface was proposed to achieve sub-diffraction focusing in the visible range. It is capable of generating sub-diffraction focal spots under left-handed circularly polarized incident light with arbitrary wavelength at the same focal plane, showing promising potentials in various applications.
Article
Physics, Multidisciplinary
Xue Jiang, JiaJie He, ChuanXin Zhang, HuaLiang Zhao, WeiQi Wang, DeAn Ta, Cheng-Wei Qiu
Summary: This study proposes a method for three-dimensional ultrasound focusing using a sparse metalens, achieving subwavelength resolution within a wide bandwidth. The sparse metalens has advantages such as three-dimensional freewheeling focusing, subwavelength resolution, and geometric simplicity, providing new possibilities for research and applications in ultrasound focusing.
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY
(2022)
Article
Physics, Multidisciplinary
Lianhong Dong, Weijie Kong, Changtao Wang, Guoyu Luo, Mingbo Pu, Xiaoliang Ma, Xiong Li, Xiangang Luo
Summary: This paper introduces an inverse design method based on super-oscillatory theory to achieve nanoscale sub-diffraction focusing metalens. By iterative topology optimization and adjoint-based inverse optimization, high-resolution focusing performance can be achieved without being limited by the initial structure distribution.
NEW JOURNAL OF PHYSICS
(2023)
Article
Optics
Miao Wang, Yu Lin, Minxue Wang, Jue-Min Yi, Xiaodong Gao, De-Yao Li, Jian-Ping Liu, Bing Cao, Chin-Hua Wang, Jian-Feng Wang, Ke Xu
Summary: We propose and demonstrate a highly efficient sub-microscale focusing technique by integrating double-sided asymmetric metasurfaces onto a GaN green laser diode. The metasurfaces consist of nanogratings on one side and a geometric phase based metalens on the other side. When integrated on the edge emission facet of the LD, linearly polarized emission is converted to circularly polarized state by the nanogratings, and the phase gradient is controlled by the metalens on the exit side. Experimental results show a sub micro-focusing from linearly polarized states with a focused spot size of about 738 nm at 520 nm wavelength and a focusing efficiency of approximately 72.8%. This research lays a foundation for various applications in optical tweezers, laser direct writing, visible light communication, and biological chip.
Article
Engineering, Mechanical
Zhiwen Ren, Hao-Wen Dong, Xudong He, Mingji Chen, Daining Fang
Summary: This study proposes a design method for underwater gradient metalenses, which can achieve broadband, high-efficiency, high-gain, and high-symmetry acoustic focusing. By optimizing the refractive index profile and using a square-latticed metamaterial, the conversion of plane waves to subwavelength focusing is achieved over a wide frequency range. Additionally, the design exhibits good environmental adaptability, making it suitable for use in high-pressure environments.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Optics
Junyi Wang, Fangfang Li, Guoguo Kang
Summary: This study demonstrates a simple method using a metasurface to achieve multiwavelength achromatic generation and focusing. By utilizing the extra degrees of freedom and multi-section design, multiwavelength achromatic super-resolution focusing in the far field has been achieved.
Article
Nanoscience & Nanotechnology
Jia Shi, Han Gao, Xing Jia, Longhuang Tang, Xianguo Li, Heli Ma, Xiuyan Li, Hua Bai, Xiang Wang, Pingjuan Niu, Jianquan Yao
Summary: In this work, an all-dielectric tunable terahertz metagrating is demonstrated, which can manipulate the diffraction of electromagnetic waves in the 6G communication window. Furthermore, a high-efficiency metalens is designed and implemented based on the all-dielectric metagrating, achieving subwavelength focusing and imaging capability.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Nanoscience & Nanotechnology
Xiao-Qiang Jiang, Wen-Hui Fan, Lv-Rong Zhao, Xu Chen, Chong Qin, Hui Yan, Qi Wu, Pei Ju
Summary: A continuously varifocal and broadband achromatic metalens (CVBAM) is proposed to address the limited functionality of current broadband achromatic metalenses (BAMs). By employing a thermally tunable material, the CVBAM can correct chromatic aberration and achieve beyond the Abbe diffraction limit for THz waves. The work may provide an advanced scheme for designing tunable BAMs and facilitate the development of THz near-field imaging and spectroscopy systems.
JOURNAL OF SCIENCE-ADVANCED MATERIALS AND DEVICES
(2023)
Article
Chemistry, Multidisciplinary
Ayato Iba, Makoto Ikeda, Valynn Katrine Mag-usara, Verdad C. Agulto, Makoto Nakajima
Summary: This paper presents a metamaterial-based super-oscillatory lens capable of generating sub-wavelength focal points at sub-THz frequencies, which is highly effective for industrial inspection applications utilizing terahertz waves.
APPLIED SCIENCES-BASEL
(2022)
Article
Physics, Applied
Yazhu Bai, Ailing Song, Chaoyu Sun, Yanxun Xiang, Fu-Zhen Xuan
Summary: In this paper, we propose a reconfigurable acoustic coding metagrating composed of rotatable open-ended round tubes for realizing broadband sound focusing with tunable focus. The proposed metagrating can precisely manipulate the focus by alternating the coding arrangements. Our work provides promising applications in acoustic imaging, medical ultrasound treatment, and nondestructive testing.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Yu Li, Xinhao Fan, Yunfeng Huang, Xuyue Guo, Liang Zhou, Peng Li, Jianlin Zhao
Summary: This paper proposes a dielectric metalens for superoscillatory focusing based on the diffraction of angular Bessel functional phase modulated vector field, providing a new solution for optical far-field label-free super-resolution imaging.
Article
Optics
Jin Chen, Hongchen Chu, Yun Lai, Huanyang Chen, Weili Song, Mingji Chen, Daining Fang
Summary: In this paper, a semi-circular gradient index lens (sGRIN) with a modified refractive index profile is proposed, achieving highly efficient achromatic subdiffraction focusing and broadband diffraction-limited far-field radiation.
PHOTONICS RESEARCH
(2021)
Article
Materials Science, Multidisciplinary
Zhixiang Wu, Jiexian Zhu, Yiyang Zou, Hu Deng, Liang Xiong, Quancheng Liu, Liping Shang
Summary: This study introduces a group of subwavelength dielectric birefringent meta-atoms for terahertz applications, providing simultaneous integration of polarization conversion and phase modulation in the 2 pi coverage range. Using the concept of optical superoscillation, a metalens with a numerical aperture of 0.975 is optimized for a wavelength of 2500 micrometers, enabling broadband polarization conversion and sub-wavelength tight focusing between 1900 and 2700 micrometers. Simulation results show spot sizes ranging from 0.418 lambda to 0.556 lambda with low sidelobe ratio and the ability to adjust focal spot size by changing incident polarization angle. The improved performance characteristics of the superoscillatory metalens demonstrate potential for various terahertz applications.
Article
Multidisciplinary Sciences
Jun Mei, Ying Wu
SCIENTIFIC REPORTS
(2019)
Article
Physics, Applied
Jun Mei, Jiqian Wang, Xiujuan Zhang, Siyuan Yu, Zhen Wang, Ming-Hui Lu
PHYSICAL REVIEW APPLIED
(2019)
Article
Physics, Multidisciplinary
Li-Yang Zheng, Vassos Achilleos, Ze-Guo Chen, Olivier Richoux, Georgios Theocharis, Ying Wu, Jun Mei, Simon Felix, Vincent Tournat, Vincent Pagneux
NEW JOURNAL OF PHYSICS
(2020)
Article
Physics, Multidisciplinary
Meng Gao, Shiqiao Wu, Jun Mei
NEW JOURNAL OF PHYSICS
(2020)
Article
Physics, Applied
Lijuan Fan, Jun Mei
PHYSICAL REVIEW APPLIED
(2020)
Article
Physics, Applied
Lijuan Fan, Jun Mei
Summary: Nonreciprocal signal operation is achieved through the use of simply structured acoustic metagratings, which provide nonreciprocal and robust circulation of the acoustic signal over a broad range of flow velocity magnitudes and profiles. The design allows for tunability, including switching between reciprocal and nonreciprocal operation, and reversing the handedness of the circulator, offering a convenient and efficient approach for the realization of nonreciprocal acoustic devices from wavelength-thick metagratings.
PHYSICAL REVIEW APPLIED
(2021)
Article
Physics, Applied
Lijuan Fan, Jun Mei
Summary: This article presents a new design approach for acoustic metagratings that can achieve different and switchable transmission and reflection functionalities of sound waves. Through a systematic design method, simultaneous and high-efficiency control over both reflected and transmitted waves is achieved, allowing for switching between different functionalities by changing operation frequency or incident angles, leading to robust and perfect wave-front manipulation effects.
PHYSICAL REVIEW APPLIED
(2021)
Article
Physics, Applied
Jun Mei, Lijuan Fan, Xiaobin Hong
Summary: In this paper, a class of elastic metagratings consisting of a one-dimensional array of elliptical hollow cylinders carved in a steel background is proposed and studied. These intelligently designed metagratings can efficiently reflect longitudinal and transverse waves and achieve various wave-front-manipulation functionalities. Different functionalities over both longitudinal and transverse waves can be realized by using the same cylinders with different rotation angles. The exhibited functionality shows robustness and is beneficial for practical applications.
PHYSICAL REVIEW APPLIED
(2022)
Article
Crystallography
Jun Mei, Lijuan Fan, Xiaobin Hong
Summary: This research proposes a simple structured metagrating that allows independent and complete control of both reflection and transmission of bulk longitudinal and transverse waves. By utilizing grating diffraction theory and genetic algorithm, the metagratings are endowed with the functionality of simultaneous and high-efficiency modulation of every reflection and transmission channel. Interesting wave-front manipulation effects are demonstrated through numerical simulations.
Correction
Physics, Multidisciplinary
Jun Mei, Lijuan Fan, Xiaobin Hong
NEW JOURNAL OF PHYSICS
(2022)
Article
Physics, Multidisciplinary
Chao Zhang, Jun Mei
Summary: Higher-order topological insulators (HOTIs) have attracted significant attention recently. This study proposes a two-dimensional square lattice spring-mass model where restoring forces between nearest neighbors can be induced by vibrations. Edge and corner states with flexible spatial distributions can be realized by tuning the elastic and inertial parameters. The work provides an easy-to-tune platform to realize HOTIs, which is useful when certain conditions are absent or difficult to achieve.
Article
Physics, Applied
Lijuan Fan, Jun Mei
Summary: We propose a compact and simple metalens design concept for high-efficiency focusing in waterborne sound transmission. The metalens consists of an open central region as a stable water flow channel and a peripheral region based on a metagrating composed of meta-atoms. By smartly designing each meta-atom, normally incident waves can be deflected towards the desired direction and focused to the focal spot, achieving subdiffraction focusing with a high energy concentration ratio. The focal depth of the metalens can be conveniently tuned by applying different velocities and directions of background water flow, and the superresolution focusing effect is sustained regardless of the presence of water flow.
PHYSICAL REVIEW APPLIED
(2023)
Article
Materials Science, Multidisciplinary
Zhanhang Du, Jun Mei
Summary: This paper proposes an intelligent design approach for a wide-angle high-efficiency retroreflector using metagrating. Compared to existing methods, the retroreflector configuration is simple and can be easily extended, making it applicable in various scenarios.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Physics, Multidisciplinary
Zhanhang Du, Jun Mei
Summary: This paper proposes the integration of acoustic metagratings with wavelength division multiplexing (WDM) technology to achieve wavelength-dependent functionalities. The study combines deep learning and particle swarm optimization to develop deterministic and probabilistic neural networks for inverse design. The results show reduced computational cost and reveal the flexibility and sensitivity of metagrating parameters.
PHYSICAL REVIEW RESEARCH
(2022)
