Ab-initio exploration of Gd monolayer interfaced with WSe$_2$: from electronic and magnetic properties to the anomalous Hall effect

TL;DR

This study investigates a Gd monolayer on WSe$_2$, revealing its electronic, magnetic, and transport properties, notably a tunable anomalous Hall effect driven by strong spin-orbit coupling and symmetry breaking.

Contribution

It provides the first ab-initio analysis of Gd/WSe$_2$ heterostructures, highlighting the origin and tunability of the anomalous Hall effect in this system.

Findings

Significant anomalous Hall conductivity observed.

AHE originates from avoided crossings near the Fermi level.

AHE tunable via lattice constant and Gd-W separation.

Abstract

Heterostructures involving transition metal dichalcogenides (TMDs) have attracted significant research interest due to the richness and versatility of the underlying physical phenomena. In this work, we investigate a heterostructure consisting of a rare-earth material, specifically a Gd monolayer, interfaced with WSe$_2$. We explore its electronic structure, magnetic properties, and transport behavior, with particular emphasis on the emergence of the anomalous Hall effect (AHE). Both Gd and W are heavy elements, providing strong spin-orbit coupling (SOC), which plays a crucial role in triggering the AHE. The combination of strong SOC and inversion symmetry breaking leads to pronounced asymmetries between the $\Gamma-K$ and $\Gamma-K^\prime$ directions in the Brillouin zone. Our calculations reveal a substantial anomalous Hall conductivity (AHC) at the ferromagnetic interface, primarily originating from numerous avoided crossings involving the d-states of both Gd and W near the Fermi level. Moreover, we demonstrate that the AHC is highly tunable, either by adjusting the in-plane lattice constant or by reducing the separation between Gd and WSe$_2$.