Sub-bandgap excitation properties of LT-GaAs-based photoconductive antennas for terahertz pulse emission and detection

Authors

Masahiko Tani Research Center for Development of Far-Infrared Region, University of Fukui

Abstract

Photoconductive antennas (PCSs) with low-temperature grown GaAs (LT-GaAs) substrate are the most commonly used for terahertz (THz) pulsed emission and detection with femtosecond laser excitations. Their sub-bandgap excitation properties are attracting much attention since cost-effective femtosecond laser sources are available in the sub-bandgap wavelength region from 1 to 1.6 μm. In this report, a systematic investigation on the properties of LT-GaAs PCA with the sub-bandgap excitations is reported. The sub-band gap excitation efficiency at wavelengths close to the bandgap of GaAs (~ 1 μm) has been found much lower than that with wavelengths at around mid-bandgap excitations (1.5 ~ 1.6 μm). This counterintuitive observation is discussed in relation with the defect states distribution in LT-GaAs.

About the Speaker

Masahiko Tani, Research Center for Development of Far-Infrared Region, University of Fukui

Masahiko Tani was born in 1964 in Nara, Japan. He graduated from Department of Physics Engineering, Kyoto University and received PhD in 1992. He worked in Kansai Advanced Research Center, Communications Research Laboratory (present National Institute of Information and Communications Technology), Japan, from 1992 to 2000 as a research scientist. He moved to Osaka University in 2000 and worked there mainly for the research of terahertz time-domain spectroscopy until 2008. He moved to University of Fukui in 2008 as a full professor. He is currently the director of Research Center for Development of Far-Infrared Region, University of Fukui, the president of Terahertz Technology Forum, Japan, and an executive board member of the Spectroscopical Society of Japan. His fields of research are terahertz sensing and spectroscopy, nonlinear optics, terahertz spintronics, and others. He has published more than 200 peer-reviewed scientific papers and his h-index is 47.

Downloads

Issue

2022: Proceedings of the 40th Samahang Pisika ng Pilipinas Physics Conference

Article ID

SPP-2022-INV-1F-01

Section

Invited Presentations

Published

2022-09-05

How to Cite

[1]

M Tani, Sub-bandgap excitation properties of LT-GaAs-based photoconductive antennas for terahertz pulse emission and detection, Proceedings of the Samahang Pisika ng Pilipinas 40, SPP-2022-INV-1F-01 (2022). URL: https://proceedings.spp-online.org/article/view/SPP-2022-INV-1F-01.