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Updated: Jun 22, 2026

Design, Fabrication, and Experimental Characterization of Plasmonic Photoconductive Terahertz Emitters
Published on: July 8, 2013
The dependence of terahertz radiation on the built-in electric field in semiconductor microstructures
Jenn-Shyong Hwang1, Hui-Ching Lin, Chin-Kuo Chang
1Dept. of Physics, National Cheng Kung University, 1 Ta-Hsueh Road, Tainan, Taiwan 70101.
Abstract:
The amplitudes of terahertz radiation are measured for a series of GaAs surface intrinsic-N(+) structures with various built-in surface electric fields as the bias. As the surface field is lower than the so-called "critical electric field" related with the energy difference between the Gamma to L valley of the semiconductor, the amplitude is proportional to the product of the surface field and the number of photo-excited carriers. As the surface field exceeds the critical field, the amplitude is independent of the surface field but proportional to the product of the critical field and the number of the photo-excited carriers.
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