The study of High-Tc superconducting THz emitting devices and its heating effect

Chiharu Watanabe; Hidetoshi Minami; Hiroyuki Kubo; Kazuki Sakamoto; Takuya Katsuragawa; Yuki Komori; Yuasa Takumi; Taiga Tanaka; Takanari Kashiwagi; Richard A. Klemm; Kazuo Kadowaki

Chiharu Watanabe
Hidetoshi Minami
Hiroyuki Kubo
Kazuki Sakamoto
Takuya Katsuragawa
Yuki Komori
Yuasa Takumi
Taiga Tanaka
Takanari Kashiwagi
Richard A. Klemm
Kazuo Kadowaki

Keywords: Superconductor, Josephson junction, hot spot

Abstract

We have measured simultaneously the spectrum of the electromagnetic wave emitted from and the local temperature of Bi₂Sr₂CaCu₂O₈₊_d rectangular mesa devices using a characteristic temperature dependent photo-luminescence (PL) intensity of SiC micro-powders, which is embrocated on the mesa surface. We succeeded in observing clear images of a hot spot where the local temperature becomes higher than T_c. Furthermore, the emission intensity was found to improve drastically, when the hot spot was dragged by the local heating of the mesa surface with a laser beam without significant changes of the emission frequency and the line width. These results strongly suggest that the higher power radiation may be attainable by adjusting the hot spot.