Seminar: Spin textured band driven colossal anisotropic magnetoresistance effect in antiferromagnetic EuTe2

Speaker: 钟志诚 研究员 (Prof. Zhicheng Zhong) (中科院宁波材料所)

Time: 10:30am, Oct. 12, 2020 (Monday)

Place: East Bldg. No.4-242, Center for Correlated Matter (Ziingang Campus)

 

Abstract

Materials with strong spin textured band (STB) emerge to be a versatile platform for developing novel advanced electronic devices. Although a lot of theories have proposed a number of materials candidates and several experiments have provided direct proof of STB effect microscopically, unravelling a real STB material with remarkable transport properties and thereby advanced functionalities has been awaited to be solved. Here, we combined thorough transport and magnetization measurement, together with theoretical calculation, to explore associated exotic properties in a STB material of EuTe2. Our study reveals strongly anisotropic coupling of electronic state (metal vs. insulator) to vector magnetic field, which leads to unprecedented colossal anisotropic magnetoresistance, (AMR) of 40000%. Density functional theory (DFT) calculation ilustrates that the insulator-to-metal transition and colossal AMR arise from the vector field dependent band structures. Our results bring the promise of STB effect into a frontier of real materials with remarkable properties and advanced functionalities and pave a path toward tantalizing STB devices.

 

报告人简介   

钟志诚研究员，国家青年千人，中科院百人。本科毕业于上海交通大学少年班，硕士毕业于北京大学，在2011年获得荷兰特文特大学博士学位。2011 年至2014年在维也纳技术大学从事博士后研究，随后在德国做洪堡学者以及马普固体物理所博士后。

近10年来一直从事关联电子材料的理论计算研究，融合了多种理论方法，包括第一性原理密度泛函理论、瓦尼尔投影、紧束缚模型、自旋轨道耦合模型、强关联模型、动态平均场理论、输运理论、以及自旋-电荷涨落理论。与多个国际知名的实验小组建立并且保持良 好的合作，多项理论预测得到了实验的证实。代表性的工作: 1) 提出氧化物界面的Rashba 通用模型Phys.Rev.B. 87, 161102 (2013); 2)提出氧化物界面的能带匹配以及电荷转移的普适规律Phys. Rev. X 7, 011023 (2017).