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Finite size effects on the quantum spin Hall state in HgTe quantum wells under two different types of boundary conditions |
Cheng Zhi (成志), Chen Rui (陈锐), Zhou Bin (周斌) |
Department of Physics, Hubei University, Wuhan 430062, China |
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Abstract The finite size effect in a two-dimensional topological insulator can induce an energy gap Eg in the spectrum of helical edge states for a strip of finite width. In a recent work, it has been found that when the spin–orbit coupling due to bulk-inversion asymmetry is taken into account, the energy gap Eg of the edge states features an oscillating exponential decay as a function of the strip width of the inverted HgTe quantum well. In this paper, we investigate the effects of the interface between a topological insulator and a normal insulator on the finite size effect in the HgTe quantum well by means of the numerical diagonalization method. Two different types of boundary conditions, i.e., the symmetric and asymmetric geometries, are considered. It is found that due to the existence of the interface between topological insulator and normal insulator this oscillatory pattern on the exponential decay induced by bulk-inversion asymmetry is modulated by the width of normal insulator regions. With the variation of the width of normal insulator regions, the shift of the Dirac point of the edge states in the spectrum and the energy gap Eg closing point in the oscillatory pattern can occur. Additionally, the effect of the spin–orbit coupling due to structure-inversion asymmetry on the finite size effects is also investigated.
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Received: 26 October 2014
Revised: 03 February 2015
Accepted manuscript online:
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PACS:
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73.43.-f
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(Quantum Hall effects)
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72.25.Dc
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(Spin polarized transport in semiconductors)
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85.75.-d
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(Magnetoelectronics; spintronics: devices exploiting spin polarized transport or integrated magnetic fields)
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Fund: Project supported by the National Natural Science Foundation of China (Grant No. 11274102), the Program for New Century Excellent Talents in University of the Ministry of Education of China (Grant No. NCET-11-0960), and the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20134208110001). |
Corresponding Authors:
Zhou Bin
E-mail: binzhou@hubu.edu.cn
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About author: 73.43.-f; 72.25.Dc; 85.75.-d |
Cite this article:
Cheng Zhi (成志), Chen Rui (陈锐), Zhou Bin (周斌) Finite size effects on the quantum spin Hall state in HgTe quantum wells under two different types of boundary conditions 2015 Chin. Phys. B 24 067304
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[1] |
Hasan M Z and Kane C L 2010 Rev. Mod. Phys. 82 3045
|
[2] |
Qi X L and Zhang S C 2011 Rev. Mod. Phys. 83 1057
|
[3] |
Kane C L and Mele E J 2005 Phys. Rev. Lett. 95 146802
|
[4] |
Kane C L and Mele E J 2005 Phys. Rev. Lett. 95 226801
|
[5] |
Yao Y, Ye F, Qi X L, Zhang S C and Fang Z 2007 Phys. Rev. B 75 041401(R)
|
[6] |
Yang Y, Xu Z, Sheng L, Wang B, Xing D Y and Sheng D N 2011 Phys. Rev. Lett. 107 066602
|
[7] |
Sheng L, Li H C, Yang Y Y, Sheng D N and Xing D Y 2013 Chin. Phys. B 22 067201
|
[8] |
Zhang Y Y, Shen M, An X T, Sun Q F, Xie X C, Chang K and Li S S 2014 Phys. Rev. B 90 054205
|
[9] |
Weber M, Hohenadler M and Assaad F F 2014 Phys. Rev. B 89 205125
|
[10] |
Bernevig B A, Hughes T L and Zhang S C 2006 Science 314 1757
|
[11] |
König M, Wiedmann S, Brüne C, Roth A, Buhmann H, Molenkamp L W, Qi X L and Zhang S C 2007 Science 318 766
|
[12] |
Roth A, Brüne C, Buhmann H, Molenkamp L W, Maciejko J, Qi X L and Zhang S C 2009 Science 325 294
|
[13] |
Brüne C, Roth A, Buhmann H, Hankiewicz E M, Molenkamp L W, Maciejko J, Qi X L and Zhang S C 2012 Nat. Phys. 8 485
|
[14] |
Nowack K C, Spanton E M, Baenninger M, Kö Buhmann H, Molenkamp L W, Goldhaber-Gordon D and Moler K A 2013 Nat. Mater. 12 787
|
[15] |
König M, Baenninger M, Garcia A G F, Harjee N, Pruitt B L, Ames C, Leubner P, Brüne C, Buhmann H, Molenkamp L W and Goldhaber-Gordon D 2013 Phys. Rev. X 3 021003
|
[16] |
Li J, Chu R L, Jain J K and Shen S Q 2009 Phys. Rev. Lett. 102 136806
|
[17] |
Yang W, Chang K and Zhang S C 2008 Phys. Rev. Lett. 100 056602
|
[18] |
Zhang L B, Zhai F and Chang K 2010 Phys. Rev. B 81 235323
|
[19] |
Chen W, Shen R, Sheng L, Wang B G and Xing D Y 2011 Phys. Rev. B 84 115420
|
[20] |
Lindner N H, Refael G and Galitski V 2011 Nat. Phys. 7 490
|
[21] |
Guo H M, Zhang X L and Feng S P 2012 Chin. Phys. B 21 117301
|
[22] |
Zhu H X, Wang T T, Gao J S, Li S, Sun Y J and Liu G L 2014 Chin. Phys. Lett. 31 030503
|
[23] |
Pang M and Wu X G 2014 Chin. Phys. B 23 077302
|
[24] |
Gao J, Liao W, Zhao H and Zhou G 2014 J. Appl. Phys. 115 023709
|
[25] |
Fu H H, Gao J H and Yao K L 2014 Nanotechnology 25 225201
|
[26] |
Michetti P, Penteado P H, Egues J C and Recher P 2012 Semicond. Sci. Techol. 27 124007
|
[27] |
Yoshimi R, Tsukazaki A, Kikutake K, Checkelsky J G, Takahashi K S, Kawasaki M and Tokura Y 2014 Nat. Mater. 13 253
|
[28] |
Fu L and Kane C L 2008 Phys. Rev. Lett. 100 096407
|
[29] |
Qi X L, Hughes T L and Zhang S C 2008 Phys. Rev. B 78 195424
|
[30] |
Seradjeh B, Moore J E and Franz M 2009 Phys. Rev. Lett. 103 066402
|
[31] |
Zhou B, Lu H Z, Chu R L, Shen S Q and Niu Q 2008 Phys. Rev. Lett. 101 246807
|
[32] |
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
|
[33] |
Cheng Z and Zhou B 2014 Chin. Phys. B 23 037304
|
[34] |
Takagaki Y 2012 J. Phys.: Condens. Matter 24 435301
|
[35] |
König M, Buhmann H, Molenkamp L W, Hughes T, Liu C X, Qi X L and Zhang S C 2008 J. Phys. Soc. Jpn. 77 031007
|
[36] |
Rothe D G, Reinthaler R W, Liu C X, Molenkamp L W, Zhang S C and Hankiewicz E M 2010 New J. Phys. 12 065012
|
[37] |
Krueckl V and Richter K 2012 Semicond. Sci. Techol. 27 124006
|
[38] |
Takagaki Y 2012 J. Phys.: Condens. Matter 24 435301
|
[39] |
Virtanen P and Recher P 2012 Phys. Rev. B 85 035310
|
[40] |
Zou Y L, Zhang L B and Song J T 2013 J. Phys.: Condens. Matter 25 075801
|
[41] |
Krueckl V and Richter K 2011 Phys. Rev. Lett. 107 086803
|
[42] |
Takagaki Y 2012 Phys. Rev. B 85 155308
|
[43] |
Ostrovsky P M, Gornyi I V and Mirlin A D 2012 Phys. Rev. B 86 125323
|
[44] |
Weithofer L and Recher P 2013 New J. Phys. 15 085008
|
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