MBE Growth and Characterization of Strained HgTe (111) Films on CdTe/GaAs
Jian Zhang1,2, Shengxi Zhang1,2, Xiaofang Qiu1, Yan Wu1**, Qiang Sun3, Jin Zou3,4, Tianxin Li1,2, Pingping Chen1,2**
1State Key Laboratory of Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 2University of Chinese Academy of Sciences, Beijing 100049 3Materials Engineering, The University of Queensland, Brisbane, Queensland 4072, Australia 4Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Queensland 4072, Australia
Abstract：Strained HgTe thin films are typical three-dimensional topological insulator materials. Most works have focused on HgTe (100) films due to the topological properties resulting from uniaxial strain. In this study, strained HgTe (111) thin films are grown on GaAs (100) substrates with CdTe (111) buffer layers using molecular beam epitaxy (MBE). The optimal growth conditions for HgTe films are determined to be a growth temperature of 160$^{\circ}\!$C and an Hg/Te flux ratio of 200. The strains of HgTe films with different thicknesses are investigated by high-resolution x-ray diffraction, including reciprocal space mapping measurements. The critical thickness of HgTe (111) film on CdTe/GaAs is estimated to be approximately 284 nm by Matthews' equations, consistent with the experimental results. Reflection high-energy electron diffraction and high-resolution transmission electron microscopy investigations indicate that high-quality HgTe films are obtained. This exploration of the MBE growth of HgTe (111) films provides valuable information for further studies of HgTe-based topological insulators.
König M, Wiedmann S, Brüne C, Roth A, Buhmann H, Molenkamp L W, Qi X L and Zhang S C 2007 Science318 766
[5]
Brüne C, Liu C X, Novik E G, Hankiewicz E M, Buhmann H, Chen Y L, Qi X L, Shen Z X, Zhang S C and Molenkamp L W 2011 Phys. Rev. Lett.106 126803
[6]
Brüne C, Roth A, Novik E G, König M, Buhmann H, Hankiewicz E M, Hanke W, Sinova J and Molenkamp L W 2010 Nat. Phys.6 448
[7]
Nowack K C, Spanton E M, Baenninger M, König M, Kirtley J R, Kalisky B, Ames C, Leubner P, Brüne C, Buhmann H, Molenkamp L W, Goldhaber-Gordon D and Moler K A 2013 Nat. Mater.12 787
[8]
Savchenko M L, Kozlov D A, Vasilev N N, Kvon Z D, Mikhailov N N, Dvoretsky S A and Kolesnikov A V 2019 Phys. Rev. B99 195423
Ballet P, Thomas C, Baudry X, Bouvier C, Crauste O, Meunier T, Badano G, Veillerot M, Barnes J P, Jouneau P H and Levy L P 2014 J. Electron. Mater.43 2955
Yang X Y, Wang G Y, Zhao C X, Zhu Z, Dong L, Li A M, Lv Y Y, Yao S H, Chen Y B, Guan D D, Li Y Y, Zheng H, Qian D, Liu C H, Chen Y L and Jia J F 2018 Chin. Phys. Lett.35 026802
[19]
Beugeling W, Kalesaki E, Delerue C, Niquet Y M, Vanmaekelbergh D and Smith C M 2015 Nat. Commun.6 6316
2020, Vol. 37 
