Electronic structure and layer-dependent magnetic order of a new high-mobility layered antiferromagnet KMnBi

Yichen Yang; Hengzhe Lu; Jian Yuan; Zhengtai Liu; Zhicheng Jiang; Zhe Huang; Jianyang Ding; Jiayu Liu; Soohyun Cho; Jishan Liu; Zhonghao Liu; Yanfeng Guo; Yi Zheng; Dawei Shen

doi:10.1088/1361-648X/acbb49

Electronic structure and layer-dependent magnetic order of a new high-mobility layered antiferromagnet KMnBi

J Phys Condens Matter. 2023 Feb 20;35(15). doi: 10.1088/1361-648X/acbb49.

Authors

Yichen Yang^{1

2}, Hengzhe Lu³, Jian Yuan^{4

5}, Zhengtai Liu^{1

2}, Zhicheng Jiang^{1

2}, Zhe Huang^{1

2}, Jianyang Ding^{1

2}, Jiayu Liu^{1

2}, Soohyun Cho^{1

2}, Jishan Liu^{1

2}, Zhonghao Liu^{1

2}, Yanfeng Guo^{4

5}, Yi Zheng³, Dawei Shen^{1

2

6}

Affiliations

¹ State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences, Shanghai 200050, People's Republic of China.
² Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
³ Zhejiang Province Key Laboratory of Quantum Technology and Device, Department of Physics, Zhejiang University, Hangzhou 310027, People's Republic of China.
⁴ School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, People's Republic of China.
⁵ ShanghaiTech Laboratory for Topological Physics, ShanghaiTech University, Shanghai 201210, People's Republic of China.
⁶ National Synchrotron Radiation Laboratory, University of Science and Technology of China, 42 South Hezuohua Road, Hefei 230029, People's Republic of China.

PMID: 36764004
DOI: 10.1088/1361-648X/acbb49

Abstract

Room-temperature two-dimensional antiferromagnetic (AFM) materials are highly desirable for various device applications. In this letter, we report the low-energy electronic structure of KMnBi measured by angle-resolved photoemission spectroscopy, which confirms an AFM ground state with the valence band maximum located at -100 meV below the Fermi level and small hole effective masses associated with the sharp band dispersion. Using complementary Raman, atomic force microscope and electric transport measurement, we systematically study the evolution of electric transport characteristics of micro-mechanically exfoliated KMnBi with varied flake thicknesses, which all consistently reveal the existence of a probable AFM ground state down to the quintuple-layer regime. The AFM phase transition temperature ranges from 220 K to 275 K, depending on the thickness. Our results suggest that with proper device encapsulation, multilayer KMnBi is indeed a promising 2D AFM platform for testing various theoretical proposals for device applications.

Keywords: ARPES; antiferromagnet; electronic structure.