Two-dimensional altermagnets: Superconductivity in a minimal microscopic model

Abstract

We propose a minimal toy model for a two-dimensional altermagnet. The model unravels altermagnetic properties at a microscopic level. We find spin-split electron and nondegenerate magnon bands with a $d$-wave symmetry. We use the model to explore magnon-mediated superconductivity in altermagnets. The dominant superconducting state is spin polarized with a $p$-wave symmetry. The state adopts its characteristics from the spin-split electron bands. Furthermore, we find that the superconducting critical temperature of altermagnets can be significantly enhanced by tuning the chemical potential.