Voltage induced switching of an antiferromagnetically ordered topological Dirac semimetal

TL;DR

This paper predicts voltage-controlled switching of the Ne9el vector in an antiferromagnetic topological Dirac semimetal by manipulating the chemical potential, leading to potential metal-insulator transitions and detectable transport signatures.

Contribution

It introduces a theoretical framework showing how chemical potential tuning can control magnetic and electronic phases in antiferromagnetic Dirac semimetals.

Findings

Chemical potential at the Dirac point favors a gapped spectrum.

Deviating the chemical potential induces a transition to a gapless phase.

Transport measurements can detect voltage-induced Ne9el vector switching.

Abstract

An antiferromagnetic semimetal has been recently identified as a new member of topological semimetals that may host three-dimensional symmetry-protected Dirac fermions. A reorientation of the N\'{e}el vector may break the underlying symmetry and open a gap in the quasi-particle spectrum, inducing the (semi)metal-insulator transition. Here, we predict that such transition may be controlled by manipulating the chemical potential location of the material. We perform both analytical and numerical analysis on the thermodynamic potential of the model Hamiltonian and find that the gapped spectrum is preferred when the chemical potential is located at the Dirac point. As the chemical potential deviates from the Dirac point, the system shows a possible transition from the gapped to the gapless phase and switches the corresponding N\'{e}el vector configuration. We perform density functional theory calculations to verify our analysis using a realistic material and discuss a two terminal transport measurement as a possible route to identify the voltage induced switching of the N\'{e}el vector.