Tunable anomalous Hall transport in bulk and two-dimensional 1$T$-CrTe$_{2}$: A first-principles study

TL;DR

This study uses first-principles calculations to explore the electronic, magnetic, and transport properties of 1$T$-CrTe$_{2}$, revealing tunable anomalous Hall effects in bulk and monolayer forms with potential for nanoscale devices.

Contribution

It demonstrates that 1$T$-CrTe$_{2}$ can be stable as a monolayer with high Curie temperature and shows how to tune its anomalous Hall effect by symmetry-breaking methods.

Findings

Monolayer 1$T$-CrTe$_{2}$ is an intrinsic ferromagnetic metal with high Curie temperature.

Both bulk and monolayer forms have vanishing anomalous Hall effect due to mirror symmetry.

Breaking mirror symmetry via magnetization direction or strain induces a sizable anomalous Hall conductivity.

Abstract

Layered materials with robust magnetic ordering have been attracting significant research interest. In recent experiments, a new layered material 1$T$-CrTe$_{2}$ has been synthesized and exhibits ferromagnetism above the room temperature. Here, based on first-principles calculations, we investigate the electronic, magnetic, and transport properties of 1$T$-CrTe$_{2}$, both in the bulk and in the two-dimensional (2D) limit. We show that 1$T$-CrTe$_{2}$ can be stable in the monolayer form, and has a low exfoliation energy. The monolayer structure is an intrinsic ferromagnetic metal, which maintains a high Curie temperature above the room temperature. Particularly, we reveal interesting features in the anomalous Hall transport. We show that in the ground state, both bulk and monolayer 1$T$-CrTe$_{2}$ possess vanishing anomalous Hall effect, because the magnetization preserves one vertical mirror symmetry. The anomalous Hall conductivity can be made sizable by tuning the magnetization direction or by uniaxial strains that break the mirror symmetry. The room-temperature 2D ferromagnetism and the tunable anomalous Hall effect make the material a promising platform for nanoscale device applications.