Open AccessAll-dielectric nanograting for increasing terahertz radiation power of photoconductive antennas
Author(s) -
Kemeng Wang,
Jianqiang Gu,
Shi Wang,
Youwen An,
Yanfeng Li,
Zhen Tian,
Chunmei Ouyang,
Jiaguang Han,
Weili Zhang
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.394600
Subject(s) - terahertz radiation , optoelectronics , photoconductivity , materials science , optics , terahertz spectroscopy and technology , dielectric , radiation , effective radiated power , physics
Photoconductive antenna (PCA) is a widely used terahertz (THz) radiation source, but its low radiated power limits the signal-to-noise ratio and bandwidth in THz imaging and spectroscopy applications. Here, we achieved significant PCA power enhancement through etching nanograting directly on the surface of the PCA substrate. The integrated nanograting not only maximizes the generation of photocarriers, but also benefits the bias electric field loaded on the photocarriers. Comparing with the conventional PCA, our PCA realizes a frequency independent THz power enhancement of 3.92 times in the range of 0.05-1.6 THz. Our results reported here not only provide a new method for increasing the THz power of PCAs, but also reveal another way that artificial nanostructures affect the PCAs, which paves the way for the subsequent researches of next-generation PCAs.