Room temperature ferromagnetism of monolayer chromium telluride with perpendicular magnetic anisotropy

TL;DR

This paper reports the successful fabrication of monolayer Cr3Te4 with room temperature ferromagnetism and perpendicular magnetic anisotropy, demonstrating potential for 2D spintronic applications.

Contribution

It introduces a scalable low-temperature growth method for 2D Cr3Te4 with room temperature ferromagnetism and out-of-plane magnetic anisotropy.

Findings

Curie temperature of ~344 K for monolayer Cr3Te4

Out-of-plane magnetic easy axis in monolayer form

Interfacial effects enhance ferromagnetic coupling

Abstract

The realization of long-range magnetic ordering in two-dimensional (2D) systems can potentially revolutionize next-generation information technology. Here, we report the successful fabrication of crystalline Cr3Te4 monolayers with room temperature ferromagnetism. Using molecular beam epitaxy, the growth of 2D Cr3Te4 films with monolayer thickness is demonstrated at low substrate temperatures (~100C), compatible with Si CMOS technology. X-ray magnetic circular dichroism measurements reveal a Curie temperature (Tc) of ~344 K for the Cr3Te4 monolayer with an out-of-plane magnetic easy axis, which decreases to ~240 K for the thicker film (~ 7 nm) with an in-plane easy axis. The enhancement of ferromagnetic coupling and the magnetic anisotropy transition is ascribed to interfacial effects, in particular the orbital overlap at the monolayer Cr3Te4/graphite interface, supported by density-functional theory calculations. This work sheds light on the low-temperature scalable growth of 2D nonlayered materials with room temperature ferromagnetism for new magnetic and spintronic devices.