Negative differential friction coefficients of two-dimensional commensurate contacts dominated by electronic phase transition  

作　　者：Kun Liu Jiangtao Cheng Xingju Zhao Yandi Zhu Xiaoyan Ren Jinlei Shi Zhengxiao Guo Chongxin Shan Hongjie Liu Shunfang Li 

机构地区：[1]Laser Fusion Research Center,Chinese Academy of Engineering Physics,Mianyang 621900,China [2]Key Laboratory of Material Physics,Ministry of Education,School of Physics and Microelectronics,Zhengzhou University,Zhengzhou 450001,China [3]Department of Chemistry and Department of Mechanical Engineering,the University of Hong Kong,Hong Kong 999077,China [4]HKU Zhejiang Institute of Research and Innovation,Qinshan SciTech City,Hangzhou 311305,China

出　　处：《Nano Research》2022年第6期5758-5766,共9页纳米研究（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.12074345,12174349,11674289,11804306,11634011 and U2030120);Henan Provincial Key Science and Technology Research Projects(No.212102210130).

摘　　要：Friction force(f)usually increases with the normal load(N)macroscopically,according to the classic law of Da Vinci–Amontons(f=μN),with a positive and finite friction coefficient(μ).Herein near-zero and negative differential friction(ZNDF)coefficients are discovered in two-dimensional(2D)van der Waals(vdW)magnetic CrI_(3)commensurate contacts.It is identified that the ferromagnetic–antiferromagnetic phase transition of the interlayer couplings of the bilayer CrI_(3)can significantly reduce the interfacial sliding energy barriers and thus contribute to ZNDF.Moreover,phase transition between the in-plane(p_(x)and p_(y))and out-of-plane(p_(z))wave-functions dominates the sliding barrier evolutions,which is attributed to the delicate interplays among the interlayer vdW,electrostatic interactions,and the intralayer deformation of the CrI_(3)layers under external load.The present findings may motivate a new concept of slide-spintronics and are expected to play an instrumental role in design of novel magnetic solid lubricants applied in various spintronic nano-devices.

关 键 词：first-principles calculations two-dimensional(2D)magnetic materials CrI_(3) negative differential friction coefficient 

分 类 号：TG1[金属学及工艺—金属学] TB3[一般工业技术—材料科学与工程]