
Study of the dipole characteristic of terahertz wave emitted from photoconductor switches
Author(s) -
Wenping Jia,
Wei Shi,
Weili Ji,
Ma De-Ming
Publication year - 2007
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.56.3845
Subject(s) - terahertz radiation , photoconductivity , semiconductor , dipole , optoelectronics , materials science , charge carrier , carrier lifetime , optics , physics , silicon , quantum mechanics
In this paperdifferent methods are used to simulate the dipole characteristic of terahertz (THz) wave emitted from low-temperature grown GaAs (LT-GaAs) and Semi-insulting GaAs (SI-GaAs) photoconductive semiconductor switches. The results indicate that the main cause of the dipole characteristic of THz wave emitted from LT-GaAs is the lifetime of optical-generated carriers being shorted than the generation time. For SI-GaAs photoconductive semiconductor switches with lifetime of optical-generated carriers longer than 100psthe dipole characteristic of THz waveforms is mainly caused by intra-valley scattering and space charge field screening under different experimental conditions (different bias field and different optical pulse energy).