High-temperature ferromagnetism in two-dimensional material MnSn originated from interlayer coupling

TL;DR

This study reveals that interlayer ferromagnetic coupling significantly enhances the Curie temperature in multilayer MnSn, a novel two-dimensional ferromagnetic material, through first-principles and Monte Carlo calculations.

Contribution

It provides a quantitative explanation for the temperature increase in multilayer MnSn due to interlayer coupling, which was previously unreported.

Findings

Curie temperature increases from 54 K to 225 K with more layers

Strong interlayer ferromagnetic coupling stabilizes ferromagnetism

Interlayer coupling acts like a magnetic field enhancing critical temperature

Abstract

MnSn monolayer synthesized recently is a novel two-dimensional ferromagnetic material with a hexagonal lattice, in which three Mn atom come together to form a trimer, making it remarkably different from other magnetic two-dimensional materials. Most impressively, there happens a sharp increase of Curie temperature from 54 K to 225 K when the number of layers increase from 1 to 3. However, no quantitative explanation is reported in previous studies. Herein, by means of first-principle calculations method and Monte carlo method, we demonstrate that strong interlayer ferromagnetic coupling is the essential role in enhancing its critical temperature, which act as a magnetic field to stabilize the ferromagnetism in the MnSn multilayers.