太赫兹辐射
光电导性
光电子学
光电流
谐振器
材料科学
电阻式触摸屏
天线(收音机)
吸收(声学)
光学
物理
电信
电气工程
计算机科学
工程类
复合材料
作者
Thomas Siday,Polina P. Vabishchevich,Lucy L. Hale,Charles Thomas Harris,Ting Shan Luk,John L. Reno,Igal Brener,Oleg Mitrofanov
出处
期刊:Nano Letters
[American Chemical Society]
日期:2019-04-04
卷期号:19 (5): 2888-2896
被引量:61
标识
DOI:10.1021/acs.nanolett.8b05118
摘要
Terahertz (THz) photoconductive devices are used for generation, detection, and modulation of THz waves, and they rely on the ability to switch electrical conductivity on a subpicosecond time scale using optical pulses. However, fast and efficient conductivity switching with high contrast has been a challenge, because the majority of photoexcited charge carriers in the switch do not contribute to the photocurrent due to fast recombination. Here, we improve efficiency of electrical conductivity switching using a network of electrically connected nanoscale GaAs resonators, which form a perfectly absorbing photoconductive metasurface. We achieve perfect absorption without incorporating metallic elements, by breaking the symmetry of cubic Mie resonators. As a result, the metasurface can be switched between conductive and resistive states with extremely high contrast using an unprecedentedly low level of optical excitation. We integrate this metasurface with a THz antenna to produce an efficient photoconductive THz detector. The perfectly absorbing photoconductive metasurface opens paths for developing a wide range of efficient optoelectronic devices, where required optical and electronic properties are achieved through nanostructuring the resonator network.
科研通智能强力驱动
Strongly Powered by AbleSci AI