Japanese Journal of Applied Physics

Submillimeter-Wave Response of Nb-YBaCuO Point-Contact Josephson Junctions

Syozo Imai, Tadayuki Tozawa, Gin-ichiro Oya, Tokukō Sugai, Yosihisa Takeuti, Nobuo Mikoshiba

Published Apr 1, 1988• 6 citations

Abstract

Shapiro steps in the submillimeter-wave (SMMW) range were observed in junctions made of a high-T c superconductor, YBa2Cu3O x (YBaCuO), and niobium. Junctions were made by pressing a Nb needle on a sintered YBaCuO disk. Shapiro steps up to the fifth order were observed for SMMWs of wavelength 871.6 µm (frequency 344.0 GHz). The dependence of the Shapiro step width on the SMMW power is in accordance with the Bessel function dependence. For SMMWs of wavelength 570.6 µm (525.4 GHz), Shapiro steps up to the second order were observed.

DOI: 10.1143/jjap.27.l522

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