The atlas of ferroicity in two-dimensional MGeX_(3) family:Room-temperature ferromagnetic half metals and unexpected ferroelectricity and ferroelasticity  

作　　者：Kuan-Rong Hao Xing-Yu Ma Hou-Yi Lyu Zhen-Gang Zhu Qing-Bo Yan Gang Su 

机构地区：[1]School of Physical Sciences,University of Chinese Academy of Sciences,Beijing,100049,China [2]School of Electronic,Electrical and Communication Engineering,University of Chinese Academy of Sciences,Beijing,100049,China [3]Center of Materials Science and Optoelectronics Engineering,College of Materials Science and Optoelectronic Technology,University of Chinese Academy of Sciences,Beijing,100049,China [4]Kavli Institute for Theoretical Sciences,and CAS Center of Excellence in Topological Quantum Computation,University of Chinese Academy of Sciences,Beijing,100190,China

出　　处：《Nano Research》2021年第12期4732-4739,共8页纳米研究（英文版）

基　　金：This work is supported in part by the National Key R&D Program of China(No.2018YFA0305800);the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB28000000);the National Natural Science Foundation of China(No.11834014);the Beijing Municipal Science and Technology Commission(No.Z118100004218001);the fundamental research funds for the central universities,and University of Chinese Academy of Sciences.

摘　　要：Two-dimensional(2D)ferromagnetic and ferroelectric materials attract unprecedented attention due to the spontaneous-symmetry-breaking induced novel properties and multifarious potential applications.Here we systematically investigate a large family(148)of 2D MGeX3(M=metal elements,X=O/S/Se/Te)by means of the high-throughput first-principles calculations,and focus on their possible ferroic properties including ferromagnetism,ferroelectricity,and ferroelasticity.We discover eight stable 2D ferromagnets including five semiconductors and three half-metals,212D antiferromagnets,and 11 stable 2D ferroelectric semiconductors including two multiferroic materials.Particularly,MnGeSe3 and MnGeTe3 are predicted to be room-temperature 2D ferromagnetic half metals with Tc of 490 and 308 K,respectively.It is probably for the first time that ferroelectricity is uncovered in 2D MGeX3 family,which derives from the spontaneous symmetry breaking induced by unexpected displacements of Ge-Ge atomic pairs,and we also reveal that the electric polarizations are in proportion to the ratio of electronegativity of X and M atoms,and IVB group metal elements are highly favored for 2D ferroelectricity.Magnetic tunnel junction and water-splitting photocatalyst based on 2D ferroic MGeX3 are proposed as examples of wide potential applications.The atlas of ferroicity in 2D MGeX3 materials will spur great interest in experimental studies and would lead to diverse applications.

关 键 词：two-dimensional materials ferroicity FERROELECTRICITY FERROELASTICITY ferromagnetic half metal 

分 类 号：TG14[一般工业技术—材料科学与工程]