The coexistence of magnetism and ferroelectricity in 3d transition metal doped SnTe monolayer

TL;DR

This study demonstrates the coexistence of ferromagnetism and ferroelectricity in transition metal-doped SnTe monolayers, offering insights for designing advanced 2D multiferroic nanoelectronic devices.

Contribution

It reveals the emergence of multiferroicity in SnTe monolayers through TM doping, highlighting the role of dopant atomic number and internal displacements.

Findings

Spontaneous spin polarization achieved via TM doping.

Both in-plane and out-of-plane ferroelectric polarization observed.

Formation energy decreases with increasing atomic number of dopants.

Abstract

The realization of multiferroicity in 2D nanomaterials is crucially important for designing advanced nanoelectronic devices such as non-volatile multistate data storage. In this work, the coexistence of ferromagnetism and ferroelectricity is reported in monolayer SnTe system by transition metal (TM) doping. Based on first-principles calculations, the spontaneous spin polarization could be realized by TM doping in ferroelectric SnTe monolayer. In addition to in-plane ferroelectric polarization, the out-of-plane ferroelectric polarization emerges in Mn (Fe)-doped SnTe monolayer due to the internal displacement of TM from the surface. Interestingly, the crystalline field centered on TM and interaction between the dopant and Te gradually enhanced with the increment of atomic number of doping elements, which explains why the formation energy decreases. The realization of multiferroics in SnTe monolayer could provide theoretical guidance for experimental preparation of low-dimensional multiferroic materials.