Phase-controllable growth of ultrathin 2D magnetic FeTe crystals

Lixing Kang; Chen Ye; Xiaoxu Zhao; Xieyu Zhou; Junxiong Hu; Qiao Li; Dan Liu; Chandreyee Manas Das; Jiefu Yang; Dianyi Hu; Jieqiong Chen; Xun Cao; Yong Zhang; Manzhang Xu; Jun Di; Dan Tian; Pin Song; Govindan Kutty; Qingsheng Zeng; Qundong Fu; Ya Deng; Jiadong Zhou; Ariando Ariando; Feng Miao; Guo Hong; Yizhong Huang; Stephen J Pennycook; Ken-Tye Yong; Wei Ji; Xiao Renshaw Wang; Zheng Liu

doi:10.1038/s41467-020-17253-x

Phase-controllable growth of ultrathin 2D magnetic FeTe crystals

Nat Commun. 2020 Jul 24;11(1):3729. doi: 10.1038/s41467-020-17253-x.

Authors

Lixing Kang^#^{1

2}, Chen Ye^#³, Xiaoxu Zhao^#⁴, Xieyu Zhou^#⁵, Junxiong Hu⁶, Qiao Li⁷, Dan Liu^{8

9}, Chandreyee Manas Das², Jiefu Yang¹, Dianyi Hu¹, Jieqiong Chen¹, Xun Cao¹, Yong Zhang¹, Manzhang Xu¹, Jun Di¹, Dan Tian¹, Pin Song¹, Govindan Kutty¹, Qingsheng Zeng¹, Qundong Fu¹, Ya Deng¹, Jiadong Zhou¹, Ariando Ariando⁶, Feng Miao⁷, Guo Hong^{8

9}, Yizhong Huang¹, Stephen J Pennycook⁴, Ken-Tye Yong¹⁰, Wei Ji¹¹, Xiao Renshaw Wang^{12

13}, Zheng Liu^{14

15

16}

Affiliations

¹ School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore.
² CINTRA CNRS/NTU/THALES, UMI 3288, Research Techno Plaza, Singapore, 637553, Singapore.
³ School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 639798, Singapore.
⁴ Department of Materials Science and Engineering, National University of Singapore, Singapore, 117575, Singapore.
⁵ Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices, Renmin University of China, 100872, Beijing, China.
⁶ Department of Physics, National University of Singapore, Singapore, 117551, Singapore.
⁷ National Laboratory of Solid State Microstructures, School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
⁸ Institute of Applied Physics and Materials Engineering, University of Macau, Macau, SAR 999078, China.
⁹ Department of Physics and Chemistry, Faculty of Science and Technology, University of Macau, Macau, SAR 999078, China.
¹⁰ CINTRA CNRS/NTU/THALES, UMI 3288, Research Techno Plaza, Singapore, 637553, Singapore. ktyong@ntu.edu.sg.
¹¹ Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices, Renmin University of China, 100872, Beijing, China. wji@ruc.edu.cn.
¹² School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 639798, Singapore. renshaw@ntu.edu.sg.
¹³ Centre for Micro-/Nano-electronics (NOVITAS), School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, 639798, Singapore. renshaw@ntu.edu.sg.
¹⁴ School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore. z.liu@ntu.edu.sg.
¹⁵ CINTRA CNRS/NTU/THALES, UMI 3288, Research Techno Plaza, Singapore, 637553, Singapore. z.liu@ntu.edu.sg.
¹⁶ Centre for Micro-/Nano-electronics (NOVITAS), School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, 639798, Singapore. z.liu@ntu.edu.sg.

^# Contributed equally.

Abstract

Two-dimensional (2D) magnets with intrinsic ferromagnetic/antiferromagnetic (FM/AFM) ordering are highly desirable for future spintronic devices. However, the direct growth of their crystals is in its infancy. Here we report a chemical vapor deposition approach to controllably grow layered tetragonal and non-layered hexagonal FeTe nanoplates with their thicknesses down to 3.6 and 2.8 nm, respectively. Moreover, transport measurements reveal these obtained FeTe nanoflakes show a thickness-dependent magnetic transition. Antiferromagnetic tetragonal FeTe with the Néel temperature (T_N) gradually decreases from 70 to 45 K as the thickness declines from 32 to 5 nm. And ferromagnetic hexagonal FeTe is accompanied by a drop of the Curie temperature (T_C) from 220 K (30 nm) to 170 K (4 nm). Theoretical calculations indicate that the ferromagnetic order in hexagonal FeTe is originated from its concomitant lattice distortion and Stoner instability. This study highlights its potential applications in future spintronic devices.