Interaction-Induced Topological Phase Transition in Magnetic Weyl Semimetals

TL;DR

This paper predicts that electron-magnon interactions in magnetic Weyl semimetals can induce topological phase transitions near the Curie temperature, with the effect depending on the Weyl nodes' spin chirality, influencing transport properties.

Contribution

It introduces the novel insight that electron-magnon interactions can destabilize Weyl nodes and cause topological phase transitions, highlighting the role of spin chirality in these processes.

Findings

Electron-magnon interactions destabilize Weyl nodes.

Topological phase transition occurs below Curie temperature.

Sensitivity of Weyl nodes depends on spin chirality.

Abstract

Despite the tremendous interest raised by the recent realization of magnetic Weyl semimetals and the observation of giant anomalous Hall signals, most of the theories used to interpret experimental data overlook the influence of magnetic fluctuations, which are ubiquitous in such materials and can massively impact topological and transport properties. In this work, we predict that in such magnetic topological systems, the interaction between electrons and magnons substantially destabilizes the Weyl nodes, leading to a topological phase transition below the Curie temperature. Remarkably, the sensitivity of the Weyl nodes to electron-magnon interaction depends on their spin chirality. We find that Weyl nodes with a trivial chirality are more sensitive to electron-magnon interactions than Weyl nodes presenting an inverted chirality, demonstrating the resilience of the latter compared to the former. Our results open perspectives for the interpretation of the transport signatures of Weyl semimetals, especially close to the Curie temperature.