Supercurrent-induced antiferromagnetic order and spin-triplet pair generation in quantum critical d-wave superconductors

TL;DR

This paper investigates how supercurrents influence magnetism and superconductivity in strongly correlated electron systems near quantum critical points, revealing supercurrent-induced antiferromagnetism and spin-triplet pairing.

Contribution

It demonstrates that supercurrents can induce antiferromagnetic order and spin-triplet pairs in a quantum critical d-wave superconductor, beyond mean-field predictions.

Findings

Supercurrent induces antiferromagnetism via Bogoliubov Fermi surfaces.

Supercurrent suppresses the superconducting gap.

Strong correlations enhance supercurrent effects.

Abstract

A supercurrent is well recognized as being of prime importance within mean-field theory, but remains largely unexplored in strongly correlated electron systems (SCES) and the quantum critical region. To clarify the impact of the supercurrent on magnetism and superconductivity near an antiferromagnetic quantum critical point, we study the two-dimensional Hubbard model based on a fluctuation exchange approximation for a current-carrying superconducting state. We show a supercurrent-induced antiferromagnetism and emergence of spin-triplet Cooper pairs. The former results from Bogoliubov Fermi surfaces, suppression in the superconducting gap, and strong correlation effects beyond the mean-field theory. Our results suggest that the supercurrent can bring out rich phenomena of superconductivity in SCES.