Reversible magnetism transition at ferroelectric oxide heterointerface  

铁电氧化物异质结界面的可逆磁转变

作　　者：Jialu Chen Zijun Zhang Liang Luo Yunhao Lu Cheng Song Di Cheng Xing Chen Wei Li Zhaohui Ren Jigang Wang He Tian Ze Zhang Gaorong Han 陈嘉璐;张子君;罗亮;陆赟豪;宋成;程荻;陈星;李玮;任召辉;王继刚;田鹤;张泽;韩高荣(State Key Laboratory of Silicon Materials,School of Materials Science and Engineering,Cyrus Tang Center for Sensor Materials and Application,Zhejiang University,Hangzhou 310027,China;Center of Electron Microscope,School of Materials Science and Engineering,Zhejiang University,Hangzhou 310027,China;Department of Physics and Astronomy,Iowa State University and Ames Laboratory-USDOE,Ames,1A 50011,USA;Department of Physics,Zhejiang University,Hangzhou 310027,China;Key Laboratory of Advanced Materials(Ministry of Education),School of Materials Science and Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]State Key Laboratory of Silicon Materials,School of Materials Science and Engineering,Cyrus Tang Center for Sensor Materials and Application,Zhejiang University,Hangzhou 310027,China [2]Center of Electron Microscope,School of Materials Science and Engineering,Zhejiang University,Hangzhou 310027,China [3]Department of Physics and Astronomy,Iowa State University and Ames Laboratory-USDOE,Ames,1A 50011,USA [4]Department of Physics,Zhejiang University,Hangzhou 310027,China [5]Key Laboratory of Advanced Materials(Ministry of Education),School of Materials Science and Engineering,Tsinghua University,Beijing 100084,China

出　　处：《Science Bulletin》2020年第24期2094-2099,M0005,共7页科学通报（英文版）

基　　金：supported by the National Natural Science Foundation of China (U1909212, U1809217, and 11474249);supported by the U.S. Department of Energy, Office of Basic Energy Science, Division of Materials Sciences and Engineering (Ames Laboratory is operated for the U.S. Department of Energy by Iowa State University under Contract No. DE-AC02-07CH11358)。

摘　　要：Oxide heterointerface is a platform to create unprecedented two-dimensional electron gas, superconductivity and ferromagnetism, arising from a polar discontinuity at the interface. In particular, the ability to tune these intriguing effects paves a way to elucidate their fundamental physics and to develop novel electronic/magnetic devices. In this work, we report for the first time that a ferroelectric polarization screening at SrTiO_(3)/PbTiO_(3) interface is able to drive an electronic construction of Ti atom, giving rise to room-temperature ferromagnetism. Surprisingly, such ferromagnetism can be switched to antiferromagnetism by applying a magnetic field, which is reversible. A coupling of itinerant electrons with local moments at interfacial Ti3d orbital was proposed to explain the magnetism. The localization of the itinerant electrons under a magnetic field is responsible for the suppression of magnetism. These findings provide new insights into interfacial magnetism and their control by magnetic field relevant interfacial electrons promising for device applications.由于极化不连续,氧化物异质界面产生了二维电子气、超导性和铁磁性等新奇物理效应.而实现这些新奇物理效应的调控则为阐明其基本物理原理和开发新颖的电子/磁性器件提供了契机.本工作报道了SrTiO_(3)/PbTiO_(3)界面处的极化屏蔽驱动Ti原子发生电子重构,从而产生室温铁磁性.进一步地,磁场可以诱导这种铁磁性与反铁磁之间的可逆转变.研究表明, SrTiO_(3)/PbTiO_(3)异质结的铁磁性源于界面处的Ti3d轨道局域磁矩与自由电子之间的耦合作用,其可逆磁转变与磁场诱导的电子局域化有关.这些发现为氧化物界面磁性的产生及其磁场调控提供了新的见解,有望为新型器件的设计与应用提供可能.

关 键 词：SrTiO3/PbTiO3 Interface Ferroelectric polarization Magnetic transition 

分 类 号：TB34[一般工业技术—材料科学与工程]