Room-temperature antiferromagnetic CrSe monolayer with tunable metal-insulator transition in ferroelectric heterostructures

TL;DR

This study discovers a stable room-temperature antiferromagnetic CrSe monolayer with a tunable metal-insulator transition in heterostructures, enabled by ferroelectric polarization, promising for spintronic applications.

Contribution

We identify a stable 2D antiferromagnetic CrSe monolayer with a high Née temperature and demonstrate a controllable metal-insulator transition in a heterostructure with ferroelectric Sc2CO2.

Findings

CrSe monolayer is thermodynamically stable and antiferromagnetic with high Née temperature.

Electric field can reversibly induce a metal-insulator transition in CrSe/Sc2CO2 heterostructure.

The transition is due to band alignment changes caused by ferroelectric polarization reversal.

Abstract

Recently, there has been a rapidly growing interest in two-dimensional (2D) transition metal chalcogenide monolayers (MLs) due to their unique magnetic and electronic properties. By using an evolutionary algorithm and first-principles calculations, we report the discovery of a previously unexplored, chemically, energetically, and thermodynamically stable 2D antiferromagnetic (AFM) CrSe ML with a N\'eel temperature higher than room temperature. Remarkably, we predict an electric field-controllable metal-insulator transition (MIT) in a van der Waals (vdW) heterostructure comprised of CrSe ML and ferroelectric Sc2CO2. This tunable transition in CrSe/Sc2CO2 heterostructure is attributed to the change in the band alignment between CrSe and Sc2CO2 caused by the ferroelectric polarization reversal in Sc2CO2. Our findings suggest that 2D AFM CrSe ML has important potential applications in AFM spintronics, particularly in the gate voltage conducting channel.