IEEE International Superconductive Electronics Conference (ISEC)

Magnetic Josephson Junctions on Nb Four-layer Structure for Half Flux Quantum Circuits

Daiki Hasegawa, Yuto Takeshita, Kyosuke Sano, Masamitsu Tanaka, Akira Fujimaki, Taro Yamashita

Published Jul 1, 2019• 4 citations

Abstract

We successfully fabricated magnetic Josephson junctions integrated on a Nb four-layer superconducting structure for demonstrating half flux quantum (HFQ) circuits. In the developed process, we adopted a 0-0-π SQUID instead of the 0-π SQUID as the basic element of the HFQ circuits. In this work, we characterized the Nb/PdNi/Nb magnetic Josephson junctions on the Nb four-layer structures fabricated by two different processes. We measured the I-V characteristics of junctions in liquid helium at 4.2 K. The results showed that the fabricated junctions had properties comparable to conventional ones on Si wafers.

DOI: 10.1109/isec46533.2019.8990908

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