Quasiparticle on Bogoliubov Fermi Surface and Odd-Frequency Cooper Pair

TL;DR

This paper explores the relationship between quasiparticles on the Bogoliubov Fermi surface and odd-frequency Cooper pairs in a superconductor with complex pairing symmetry, revealing coexistence and detailed symmetry properties.

Contribution

It demonstrates the coexistence of odd-frequency pairs with quasiparticles on the Bogoliubov Fermi surface in a superconductor with j=3/2 electrons and analyzes their symmetry in realistic cubic systems.

Findings

Quasiparticles on the Bogoliubov Fermi surface are linked to odd-frequency Cooper pairs.

Odd-frequency pairs characterized by chirality coexist with Bogoliubov Fermi surface quasiparticles.

Symmetry analysis of odd-frequency pairs in cubic superconductors is provided.

Abstract

We discuss a close relationship between a quasiparticle on the Bogoliubov Fermi surface and an odd-frequency Cooper pair in a superconductor in which a Cooper pair consisting of two j=3/2 electrons forms the pseudospin-quintet even-parity pair potential with breaking time-reversal symmetry. It has been established in a single-band superconductor that a low-energy quasiparticle below the superconducting gap accompanies an odd-frequency Cooper pair. In this paper, we show that an odd-frequency pair characterized by chirality coexists with a quasiparticle on the Bogoliubov Fermi surface. The symmetry of odd-frequency Cooper pairs is analyzed in detail by taking realistic pair potentials into account in a cubic superconductor.