Altermagnetism from interaction-driven itinerant magnetism

TL;DR

This paper introduces a new mechanism for altermagnetism driven by the interplay of local electron interactions and itinerant magnetism, highlighting its stability and tunability for spintronic applications.

Contribution

It proposes a novel interaction-driven mechanism for altermagnetism, expanding the understanding of how to identify and tune such materials for device use.

Findings

Altermagnetism remains stable across various interactions and dopings.

The spin-charge conversion ratio can be effectively tuned.

The mechanism offers a new pathway for designing altermagnetic materials.

Abstract

Altermagnetism, a new phase of collinear spin-order sharing similarities with antiferromagnets and ferromagnets, has introduced a new guiding principle for spintronic/thermoelectric applications due to its direction-dependent magnetic properties. Fulfilling the promise to exploit altermagnetism for device design depends on identifying materials with tuneable transport properties. The search for intrinsic altermagnets has so far focused on the role of anisotropy in the crystallographic symmetries and in the bandstructure. Here, we present a different mechanism that approaches this goal by leveraging the interplay between a Hubbard local repulsion and the itinerant magnetism given by the presence of van Hove singularities. We show that altermagnetism is stable for a broad range of interactions and dopings and we focus on tunability of the spin-charge conversion ratio.