Pairing symmetry of superconductivity coexisting with antiferromagnetism

TL;DR

This paper investigates the pairing symmetry in superconductors coexisting with antiferromagnetism, revealing the possibility of odd-frequency spin-triplet s-wave pairing through microscopic calculations.

Contribution

It demonstrates that odd-frequency spin-triplet s-wave pairing can occur in such systems, challenging conventional expectations about pairing symmetry in antiferromagnetic superconductors.

Findings

Odd-frequency spin-triplet s-wave pairing is possible.

Contradicts the expectation that antiferromagnetism favors spin-singlet d-wave pairing.

Uses microscopic theory and RPA in the Hubbard model to derive results.

Abstract

Pairing symmetry in the superconducting state coexisting with antiferromagnetic order is studied based on a microscopic theory. We calculate the linearized Eliashberg's equation within the random phase approximation in the Hubbard model with a staggered field. We find that odd-frequency spin-triplet (equal-spin) s-wave pairing state can be realized. This result contradicts a naive expectation that antiferromagnetic order induces antiferromagnetic spin fluctuation and favors spin-singlet d-wave pairing as in the standard strongly correlated systems.