IEEE Transactions on Applied Superconductivity

High T/sub c/ superconducting step-edge junctions and their properties in millimeter-wave band

Yijun Feng, L. Kang, X. B. Wang, Shuzhen Yang, Jianping Zuo, H.B. Wang, Weiwei Xu, Qilin Cheng, Pan Wu, S.L. Yan, Lei Zhou

Published Jun 1, 1995• 1 citation

Publisher

Abstract

Superconducting step-edge junctions were fabricated on step-edges in (100) LaAlO/sub 3/ substrates by sputter-deposited epitaxial YBaCuO and TlBaCaCuO thin films. The substrate steps were patterned by ion beam etching using metal film as a mask. The transport properties of the junctions were characterized by four-probe electrical measurements. The critical current-normal resistance product (I/sub c/R/sub N/) was larger than 0.2 mV (77 K) for most of the junctions. Clear Shapiro steps were observed in the current-voltage characteristics of the junctions with 36 GHz or 95 GHz millimeter-wave irradiation. The high frequency properties of these high T/sub c/ Josephson junctions showed that they were quite suitable for the Josephson harmonic mixer used in the digital phase locked millimeter and sub-millimeter wave sources.>

DOI: 10.1109/77.403172

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