Tuning 2D magnetism in Fe_(3+X)GeTe_(2) films by element doping  

作　　者：Shanshan Liu Zihan Li Ke Yang Enze Zhang Awadhesh Narayan Xiaoqian Zhang Jiayi Zhu Wenqing Liu Zhiming Liao Masaki Kudo Takaaki Toriyama Yunkun Yang Qiang Li Linfeng Ai Ce Huang Jiabao Sun Xiaojiao Guo Wenzhong Bao Qingsong Deng Yanhui Chen Lifeng Yin Jian Shen Xiaodong Han Syo Matsumura Jin Zou Yongbing Xu Xiaodong Xu Hua Wu Faxian Xiu 

机构地区：[1]State Key Laboratory of Surface Physics and Department of Physics,Fudan University,Shanghai 200433,China [2]Institute for Nanoelectronic Devices and Quantum Computing,Fudan University,Shanghai 200433,China [3]College of Science,University of Shanghai for Science and Technology,Shanghai 200093,China [4]Laboratory for Computational Physical Sciences(MOE),Fudan University,Shanghai 200433,China [5]Solid State and Structural Chemistry Unit,Indian Institute of Science,Bangalore 560012,India [6]School of Electronic Science and Engineering,Nanjing University,Nanjing 210093,China [7]Department of Physics,University of Washington,Seattle,WA 98195-1560,USA [8]Department of Electronic Engineering,Royal Holloway University of London,Egham TW200EX,UK [9]Materials Engineering,The University of Queensland,Brisbane QLD 4072,Australia [10]Beijing Key Laboratory of Microstructure and Property of Advanced Materials,Institute of Microstructure and Property of Advanced Materials,Beijing University of Technology,Beijing 100124,China [11]The Ultramicroscopy Research Center,Kyushu University,Fukuoka 819-0395,Japan [12]State Key Laboratory of ASIC and System,School of Microelectronics,Fudan University,Shanghai 200433,China [13]Collaborative Innovation Center of Advanced Microstructures,Nanjing 210093,China [14]Department of Applied Quantum Physics and Nuclear Engineering,Kyushu University,Fukuoka 819-0395,Japan [15]Centre for Microscopy and Microanalysis,The University of Queensland,Brisbane QLD 4072,Australia [16]Shanghai Research Center for Quantum Sciences,Shanghai 201315,China

出　　处：《National Science Review》2022年第6期158-165,共8页国家科学评论（英文版）

基　　金：supported by the National Key Research and Development Program of China (2017YFA0303302,2018YFA0305601, 2016YFA0300700 and 2017YFA0206304);the National Natural Science Foundation of China (11934005,61322407, 11874116, 11474059, 11674064, 61427812 and11774160);the Science and Technology Commission of Shanghai (19511120500);the Shanghai Municipal Science and Technology Major Project (2019SHZDZX01);the Program of Shanghai Academic/Technology Research Leader(20XD1400200);the Beijing Natural Science Foundation(Z180014);the National Basic Research Program of China(2014CB921101 and 2016YFA0300803);the UK EPSRC(EP/S010246/1);the Australian Research Council,the Progress100 program to encourage the UQ-KU collaboration;the Japanese Nanotechnology Platform Project for advanced nanostructure characterization (JPMXP09-A-19-KU-0312);support from the China Postdoctoral Innovative Talents Support Program (BX20190085);the China Postdoctoral Science Foundation (2019M661331);support from the China Postdoctoral Science Foundation (2020TQ0080 and 2020M681138);support from the startup grant (SG/MHRD-19–0001)of the Indian Institute of Science;the University of Washington is supported by the Department of Energy,Basic Energy Sciences,Materials Sciences and Engineering Division(DE-SC0018171)。

摘　　要：Two-dimensional(2D)ferromagnetic materials have been discovered with tunable magnetism and orbital-driven nodal-line features.Controlling the 2D magnetism in exfoliated nanoflakes via electric/magnetic fields enables a boosted Curie temperature(T_(C))or phase transitions.One of the challenges,however,is the realization of high T_(C) 2D magnets that are tunable,robust and suitable for large scale fabrication.Here,we report molecular-beam epitaxy growth of wafer-scale Fe_(3+X)GeTe_(2) films with T_(C) above room temperature.By controlling the Fe composition in Fe_(3+X)GeTe_(2),a continuously modulated T_(C) in a broad range of 185–320 K has been achieved.This widely tunable TC is attributed to the doped interlayer Fe that provides a 40%enhancement around the optimal composition X=2.We further fabricated magnetic tunneling junction device arrays that exhibit clear tunneling signals.Our results show an effective and reliable approach,i.e.element doping,to producing robust and tunable ferromagnetism beyond room temperature in a large-scale 2D Fe_(3+X)GeTe_(2) fashion.

关 键 词：2D ferromagnetic material Fe_(3+X)GeTe_(2)film element doping above room temperature TC tunability 

分 类 号：O469[理学—凝聚态物理] TB383.2[理学—电子物理学]