Author(s): Sun, JH (Sun, Jinhai); Cai, H (Cai, He); Li, MD (Li, Mingde); Xu, Y (Xu, Yun); Lu, GZ (Lu, Guizhen); Zhang, XT (Zhang, Xutao); Liu, YQ (Liu, Yongqiang)

Source: OPTIK Volume: 227 Article Number: 166021 DOI: 10.1016/j.ijleo.2020.166021 Published: FEB 2021

Abstract: The laser electric field distribution, carrier distribution and photoconductive current densities under different electric field intensities in low temperature grown GaAs (LT-GaAs) layer of photoconductive antenna (PCA) have been simulated by finite element method. When a plasmoninduced PCA is pumped by an 800 nm laser beam, the plasmon on the interface of air and LT-GaAs aids the conversion of more laser photons into photo-generated carriers and thus increases the density of the photo-current leading to a higher-power terahertz pulse. A quadratic function fitting relationship between the laser electric field intensity and the maximum density of photoconductive current has been obtained for the first time. On this basis, a plasmon-induced terahertz PCA has been designed and packaged using electron beam exposure technology. The enhancement effect on photo-electric conversion efficiency of plasmon in PCA is verified by comparing terahertz radiation spectra from conventional and plasmon-induced PCAs. The terahertz radiation properties of two kinds of PCAs fabricated on an identical LT-GaAs layer were evaluated by means of terahertz time-domain spectroscopy.

Accession Number: WOS:000651298800005

ISSN: 0030-4026

eISSN: 1618-1336

Full Text: https://www.sciencedirect.com/science/article/pii/S0030402620318337?via%3Dihub