Phonon-mediated spin-polarized superconductivity in altermagnets

TL;DR

This paper explores the potential for phonon-mediated unconventional superconductivity in altermagnets, revealing a dominant odd-momentum, spin-polarized pairing instability due to unique spin and momentum structures.

Contribution

It introduces a minimal Lieb lattice model for altermagnets and demonstrates a novel spin-polarized superconducting instability mediated by phonons.

Findings

Identification of a dominant odd-momentum, spin-polarized pairing instability.

Explanation of the instability's origin in spin-structure and phonon interactions.

Insight into unconventional superconductivity in altermagnets.

Abstract

We consider the possibility of phonon-mediated unconventional superconductivity in a recently discovered new class of antiferromagnets, dubbed altermagnets. Within a weak-coupling approach, and using a minimal Lieb lattice model for altermagnets, we find a dominant superconducting instability odd in momentum and even in spin with spin-polarized Cooper pairs. We discuss the origin of this unusual result in terms of the spin-structure of the altermagnetic Fermi surface, in combination with the momentum-space structure of the effective phonon-mediated electron-electron interactions on the Fermi surface.