Fabrication of submicron La$_{2-x}$Sr$_{x}$CuO$_{4}$ intrinsic Josephson junction stacks

Yuimaru Kubo; Yamaguchi Takahide; Takayoshi Tanaka; Shinya Ueda; Satoshi Ishii; Shunsuke Tsuda; A. T. M. Nazmul Islam; Isao Tanaka; Yoshihiko Takano

doi:10.1063/1.3544037

arXiv · 1108.3469

Fabrication of submicron La$_{2-x}$Sr$_{x}$CuO$_{4}$ intrinsic Josephson junction stacks

Yuimaru Kubo·Yamaguchi Takahide·Takayoshi Tanaka·Shinya Ueda·Satoshi Ishii·Shunsuke Tsuda·A. T. M. Nazmul Islam·Isao Tanaka·Yoshihiko Takano

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Abstract

Intrinsic Josephson junction (IJJ) stacks of cuprate superconductors have potential to be implemented as intrinsic phase qubits working at relatively high temperatures. We report success in fabricating submicron La$_{2-x}$Sr$_{x}$CuO$_{4}$ (LSCO) IJJ stacks carved out of single crystals. We also show a new fabrication method in which argon ion etching is performed after focused ion beam etching. As a result, we obtained an LSCO IJJ stack in which resistive multi-branches appeared. It may be possible to control the number of stacked IJJs with an accuracy of a single IJJ by developing this method.

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Yuimaru Kubo, Yamaguchi Takahide, Takayoshi Tanaka, Shinya Ueda, Satoshi Ishii, Shunsuke Tsuda, A. T. M. Nazmul Islam, Isao Tanaka, Yoshihiko Takano. 2011-08-17. Fabrication of submicron La$_{2-x}$Sr$_{x}$CuO$_{4}$ intrinsic Josephson junction stacks. https://doi.org/10.1063/1.3544037

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