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arXiv · 2102.13463

1550 nm compatible ultrafast photoconductive material based on a GaAs/ErAs/GaAs heterostructure

Kedong Zhang·Yiwen Li·Yifeng Ren·Xing Fan·Chen Li·Jianfei Li·Yafei Meng·Yu Deng·Fengqiu Wang·Hong Lu·Yan-Feng Chen
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Abstract

The sub-bandgap absorption and ultrafast relaxation in a GaAs/ErAs/GaAs heterostructure are reported. The infrared absorption and 1550 nm-excited ultrafast photo-response are studied by Fourier transform infrared (FTIR) spectrometry and time-domain pump-probe technique. The two absorption peaks located at 2.0 um (0.62 eV) and 2.7 um (0.45 eV) are originated from the ErAs/GaAs interfacial Schottky states and sub-bandgap transition within GaAs, respectively. The photo-induced carrier lifetime, excited using 1550 nm light, is measured to be as low as 190 fs for the GaAs/ErAs/GaAs heterostructure, making it a promising material for 1550-nm-technology-compatible, high critical-breakdown-field THz devices. The relaxation mechanism is proposed and the functionality of ErAs is revealed.

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Kedong Zhang, Yiwen Li, Yifeng Ren, Xing Fan, Chen Li, Jianfei Li, Yafei Meng, Yu Deng, Fengqiu Wang, Hong Lu, Yan-Feng Chen. 2021-02-26. 1550 nm compatible ultrafast photoconductive material based on a GaAs/ErAs/GaAs heterostructure. https://arxiv.org/abs/2102.13463

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