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arXiv · 2101.07478

Josephson effect of superconductors with $J=3/2$ electrons

Dakyeong Kim·Shingo Kobayashi·Yasuhiro Asano
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Abstract

The angular momentum of an electron is characterized well by pseudospin with $J=3/2$ in the presence of strong spin-orbit interactions. We study theoretically the Josephson effect of superconductors in which such two $J=3/2$ electrons form a Cooper pair. Within even-parity symmetry class, pseudospin-quintet pairing states with $J=2$ can exist as well as pseudospin-singlet state with $J=0$. We focus especially on the Josephson selection rule among these even-parity superconductors. We find that the selection rule between quintet states is severer than that between spin-triplet states formed by two $S=1/2$ electrons. The effects of a pseudospin-active interface on the selection rule are discussed as well as those of odd-frequency Cooper pairs generated by pseudospin dependent band structures.

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Dakyeong Kim, Shingo Kobayashi, Yasuhiro Asano. 2021-01-19. Josephson effect of superconductors with $J=3/2$ electrons. https://doi.org/10.1103/physrevb.103.184516

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