Electrically Tunable Terahertz Focusing Modulator Enabled by Liquid Crystal Integrated Dielectric Metasurface
Active lenses with focal tunable properties are highly desired in the modern imaging systems from the visible to the microwaves. In this paper, we demonstrate a terahertz (THz) lens with electrically switchable focal length. It is composed of a large-birefringence liquid crystal (LC) layer infiltrat...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-05-01
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| Series: | Crystals |
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| Online Access: | https://www.mdpi.com/2073-4352/11/5/514 |
| _version_ | 1797535066044235776 |
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| author | Yanchun Shen Zhixiong Shen Yuye Wang Degang Xu Wei Hu |
| author_facet | Yanchun Shen Zhixiong Shen Yuye Wang Degang Xu Wei Hu |
| author_sort | Yanchun Shen |
| collection | DOAJ |
| description | Active lenses with focal tunable properties are highly desired in the modern imaging systems from the visible to the microwaves. In this paper, we demonstrate a terahertz (THz) lens with electrically switchable focal length. It is composed of a large-birefringence liquid crystal (LC) layer infiltrating a dielectric metasurface. When the birefringence of LC is tuned with an external bias, the phase shift of a single meta-unit will change. With parameter sweep using the finite-different time-domain (FDTD) simulation method, meta-units with varying geometries are optimized to achieve a focal length switchable metalens. The numerical results show that the focal length can be switched between 8.3 mm and 10.5 mm at bias OFF and ON states, respectively, which is consistent with the design. A feasible fabrication procedure of the lens is further discussed. Such a device can be designed beyond the THz band to the visible or the microwaves, and may be widely applied in integrated imaging systems. |
| first_indexed | 2024-03-10T11:39:45Z |
| format | Article |
| id | doaj.art-3595670b20fa4d6a8b79816ca67ef9ab |
| institution | Directory Open Access Journal |
| issn | 2073-4352 |
| language | English |
| last_indexed | 2024-03-10T11:39:45Z |
| publishDate | 2021-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Crystals |
| spelling | doaj.art-3595670b20fa4d6a8b79816ca67ef9ab2023-11-21T18:34:07ZengMDPI AGCrystals2073-43522021-05-0111551410.3390/cryst11050514Electrically Tunable Terahertz Focusing Modulator Enabled by Liquid Crystal Integrated Dielectric MetasurfaceYanchun Shen0Zhixiong Shen1Yuye Wang2Degang Xu3Wei Hu4Information Engineering Institute, Guangzhou Railway Polytechnic, Guangzhou 510432, ChinaKey Laboratory of Intelligent Optical Sensing and Manipulation, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, ChinaInstitute of Laser and Optoelectronics, School of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin 300072, ChinaInstitute of Laser and Optoelectronics, School of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin 300072, ChinaKey Laboratory of Intelligent Optical Sensing and Manipulation, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, ChinaActive lenses with focal tunable properties are highly desired in the modern imaging systems from the visible to the microwaves. In this paper, we demonstrate a terahertz (THz) lens with electrically switchable focal length. It is composed of a large-birefringence liquid crystal (LC) layer infiltrating a dielectric metasurface. When the birefringence of LC is tuned with an external bias, the phase shift of a single meta-unit will change. With parameter sweep using the finite-different time-domain (FDTD) simulation method, meta-units with varying geometries are optimized to achieve a focal length switchable metalens. The numerical results show that the focal length can be switched between 8.3 mm and 10.5 mm at bias OFF and ON states, respectively, which is consistent with the design. A feasible fabrication procedure of the lens is further discussed. Such a device can be designed beyond the THz band to the visible or the microwaves, and may be widely applied in integrated imaging systems.https://www.mdpi.com/2073-4352/11/5/514dielectric metasurfaceliquid crystalfocal tunable lensterahertz |
| spellingShingle | Yanchun Shen Zhixiong Shen Yuye Wang Degang Xu Wei Hu Electrically Tunable Terahertz Focusing Modulator Enabled by Liquid Crystal Integrated Dielectric Metasurface Crystals dielectric metasurface liquid crystal focal tunable lens terahertz |
| title | Electrically Tunable Terahertz Focusing Modulator Enabled by Liquid Crystal Integrated Dielectric Metasurface |
| title_full | Electrically Tunable Terahertz Focusing Modulator Enabled by Liquid Crystal Integrated Dielectric Metasurface |
| title_fullStr | Electrically Tunable Terahertz Focusing Modulator Enabled by Liquid Crystal Integrated Dielectric Metasurface |
| title_full_unstemmed | Electrically Tunable Terahertz Focusing Modulator Enabled by Liquid Crystal Integrated Dielectric Metasurface |
| title_short | Electrically Tunable Terahertz Focusing Modulator Enabled by Liquid Crystal Integrated Dielectric Metasurface |
| title_sort | electrically tunable terahertz focusing modulator enabled by liquid crystal integrated dielectric metasurface |
| topic | dielectric metasurface liquid crystal focal tunable lens terahertz |
| url | https://www.mdpi.com/2073-4352/11/5/514 |
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