中国物理B ›› 2016, Vol. 25 ›› Issue (9): 94222-094222.doi: 10.1088/1674-1056/25/9/094222

• SPECIAL TOPIC—Physical research in liquid crystal • 上一篇    下一篇

Bridging the terahertz near-field and far-field observations of liquid crystal based metamaterial absorbers

Lei Wang(王磊), Shijun Ge(葛士军), Zhaoxian Chen(陈召宪), Wei Hu(胡伟), Yanqing Lu(陆延青)   

  1. 1. National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures and College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, Chin;
    2. School of Optoelectronic Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, China
  • 收稿日期:2016-05-18 出版日期:2016-09-05 发布日期:2016-09-05
  • 通讯作者: Yanqing Lu E-mail:yqlu@nju.edu.cn
  • 基金资助:
    Project supported by the National Basic Research Program of China (Grant No. 2012CB921803), the National Natural Science Foundation of China (Grants Nos. 61225026, 61490714, 11304151, and 61435008), the Natural Science Foundation of Jiangsu Province, China (Grant Nos. BK20150845 and 15KJB140004), the Open Foundation Project of National Laboratory of Solid State Microstructures, China (Grant No. M28003), and the Research Center of Optical Communications Engineering & Technology, Jiangsu Province, China.

Bridging the terahertz near-field and far-field observations of liquid crystal based metamaterial absorbers

Lei Wang(王磊)1,2, Shijun Ge(葛士军)1, Zhaoxian Chen(陈召宪)1, Wei Hu(胡伟)1, Yanqing Lu(陆延青)1   

  1. 1. National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures and College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, Chin;
    2. School of Optoelectronic Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, China
  • Received:2016-05-18 Online:2016-09-05 Published:2016-09-05
  • Contact: Yanqing Lu E-mail:yqlu@nju.edu.cn
  • Supported by:
    Project supported by the National Basic Research Program of China (Grant No. 2012CB921803), the National Natural Science Foundation of China (Grants Nos. 61225026, 61490714, 11304151, and 61435008), the Natural Science Foundation of Jiangsu Province, China (Grant Nos. BK20150845 and 15KJB140004), the Open Foundation Project of National Laboratory of Solid State Microstructures, China (Grant No. M28003), and the Research Center of Optical Communications Engineering & Technology, Jiangsu Province, China.

摘要: Metamaterial-based absorbers play a significant role in applications ranging from energy harvesting and thermal emitters to sensors and imaging devices. The middle dielectric layer of conventional metamaterial absorbers has always been solid. Researchers could not detect the near field distribution in this layer or utilize it effectively. Here, we use anisotropic liquid crystal as the dielectric layer to realize electrically fast tunable terahertz metamaterial absorbers. We demonstrate strong, position-dependent terahertz near-field enhancement with sub-wavelength resolution inside the metamaterial absorber. We measure the terahertz far-field absorption as the driving voltage increases. By combining experimental results with liquid crystal simulations, we verify the near-field distribution in the middle layer indirectly and bridge the near-field and far-field observations. Our work opens new opportunities for creating high-performance, fast, tunable, terahertz metamaterial devices that can be applied in biological imaging and sensing.

关键词: liquid crystal, terahertz, metamaterial absorber, near-field and far-field properties

Abstract: Metamaterial-based absorbers play a significant role in applications ranging from energy harvesting and thermal emitters to sensors and imaging devices. The middle dielectric layer of conventional metamaterial absorbers has always been solid. Researchers could not detect the near field distribution in this layer or utilize it effectively. Here, we use anisotropic liquid crystal as the dielectric layer to realize electrically fast tunable terahertz metamaterial absorbers. We demonstrate strong, position-dependent terahertz near-field enhancement with sub-wavelength resolution inside the metamaterial absorber. We measure the terahertz far-field absorption as the driving voltage increases. By combining experimental results with liquid crystal simulations, we verify the near-field distribution in the middle layer indirectly and bridge the near-field and far-field observations. Our work opens new opportunities for creating high-performance, fast, tunable, terahertz metamaterial devices that can be applied in biological imaging and sensing.

Key words: liquid crystal, terahertz, metamaterial absorber, near-field and far-field properties

中图分类号:  (Display devices, liquid-crystal devices)

  • 42.79.Kr
81.05.Xj (Metamaterials for chiral, bianisotropic and other complex media) 42.25.Bs (Wave propagation, transmission and absorption)