Discovery of Two-Dimensional Multiferroicity in van der Waals CuCrP2S6 Layers

Multiferroic materials are potential to be applied in novel magnetoelectric devices, for example, high-density non-volatile storage. Last decades, research on multiferroic materials was focused on three-dimensional (3D) materials. However, 3D materials suffer from the dangling bonds and quantum tunn...

Full description

Saved in:
Bibliographic Details
Published in:arXiv.org 2019-02
Main Authors: Lai, Youfang, Song, Zhigang, Wan, Yi, Xue, Mingzhu, Yu, Ye, Dai, Lun, Yang, Wenyun, Du, Honglin, Yang, jinbo
Format: Article
Language:English
Subjects:
Antiferroelectricity
Electric dipoles
Electric fields
Ferroelectric materials
Ferroelectricity
Ferromagnetism
First principles
Hysteresis loops
Mathematical analysis
Monolayers
Multiferroic materials
Quantum tunnelling
Thin films
Two dimensional materials
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Multiferroic materials are potential to be applied in novel magnetoelectric devices, for example, high-density non-volatile storage. Last decades, research on multiferroic materials was focused on three-dimensional (3D) materials. However, 3D materials suffer from the dangling bonds and quantum tunneling in the nano-scale thin films. Two-dimensional (2D) materials might provide an elegant solution to these problems, and thus are highly on demand. Using first-principles calculations, we predict ferromagnetism and driven ferroelectricity in the monolayer and even a few-layers of CuCrP2S6. Although the total energy of the ferroelectric phase of monolayer is higher than that of the antiferroelectric phase, the ferroelectric phases can be realized by applying a large electric field. Besides the degrees of freedoms in the common multiferroic materials, the valley degree of freedom is also polarized according to our calculations. The spins, electric dipoles and valleys are coupled with each other as shown in the computational results. In experiment, we observe the out-of-plane ferroelectricity in a few-layer CuCrP2S6 (approximately 13 nm thick) at room temperature. 2D ferromagnetism of few-layers is inferred from magnetic hysteresis loops of the massively stacked nanosheets at 10 K. The experimental observations support our calculation very well. Our findings may provide a series of 2D materials for further device applications.
ISSN:2331-8422