Dirac-Screening Stabilized Surface-State Transport in a Topological Insulator

被引：55

作者：

Bruene, Christoph ^{[1
]}

Thienel, Cornelius ^{[1
]}

Stuiber, Michael ^{[1
]}

Boettcher, Jan ^{[2
]}

Buhmann, Hartmut ^{[1
]}

Novik, Elena G. ^{[1
]}

Liu, Chao-Xing ^{[3
]}

Hankiewicz, Ewelina M. ^{[2
]}

Molenkamp, Laurens W. ^{[1
]}

机构：

[1] Univ Wurzburg, Phys Inst EP3, D-97074 Wurzburg, Germany

[2] Univ Wurzburg, Inst Theoret Phys & Astrophys TP4, D-97074 Wurzburg, Germany

[3] Penn State Univ, University Pk, PA 16802 USA

来源：

PHYSICAL REVIEW X | 2014年 / 4卷 / 04期

关键词：

HGTE QUANTUM-WELLS; PHASE;

D O I：

10.1103/PhysRevX.4.041045

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We report magnetotransport studies on a gated strained HgTe device. This material is a three-dimensional topological insulator and exclusively shows surface-state transport. Remarkably, the Landaulevel dispersion and the accuracy of the Hall quantization remain unchanged over a wide density range (3 x 10(11) cm(-2) < n < 2 x 10(12) cm(-2)). These observations imply that even at large carrier densities, the transport is surface-state dominated, where bulk transport would have been expected to coexist already. Moreover, the density dependence of the Dirac-type quantum Hall effect allows us to identify the contributions from the individual surfaces. A k . p model can describe the experiments but only when assuming a steep band bending across the regions where the topological surface states are contained. This steep potential originates from the specific screening properties of Dirac systems and causes the gate voltage to influence the position of the Dirac points rather than that of the Fermi level.

引用

页数：6

共 20 条

[1] RESTSTRAHLEN SPECTRA OF HGTE AND CDXHG1-XTE [J].

BAARS, J ;

SORGER, F .

SOLID STATE COMMUNICATIONS, 1972, 10 (09) :875-&

[2] Self-consistent k . p calculations for gated thin layers of three-dimensional topological insulators [J].

Baum, Yuval ;

Boettcher, Jan ;

Bruene, Christoph ;

Thienel, Cornelius ;

Molenkamp, Laurens W. ;

Stern, Ady ;

Hankiewicz, Ewelina M. .

PHYSICAL REVIEW B, 2014, 89 (24)

[3] Quantum spin Hall effect and topological phase transition in HgTe quantum wells [J].

Bernevig, B. Andrei ;

Hughes, Taylor L. ;

Zhang, Shou-Cheng .

SCIENCE, 2006, 314 (5806) :1757-1761

[4] Quantum Hall Effect from the Topological Surface States of Strained Bulk HgTe [J].

Bruene, C. ;

Liu, C. X. ;

Novik, E. G. ;

Hankiewicz, E. M. ;

Buhmann, H. ;

Chen, Y. L. ;

Qi, X. L. ;

Shen, Z. X. ;

Zhang, S. C. ;

Molenkamp, L. W. .

PHYSICAL REVIEW LETTERS, 2011, 106 (12)

[5]

Brüne C, 2012, NAT PHYS, V8, P485, DOI [10.1038/NPHYS2322, 10.1038/nphys2322]

[6] Helical edge and surface states in HgTe quantum wells and bulk insulators [J].

Dai, Xi ;

Hughes, Taylor L. ;

Qi, Xiao-Liang ;

Fang, Zhong ;

Zhang, Shou-Cheng .

PHYSICAL REVIEW B, 2008, 77 (12)

[7] NEGATIVE COMPRESSIBILITY OF INTERACTING 2-DIMENSIONAL ELECTRON AND QUASI-PARTICLE GASES [J].

EISENSTEIN, JP ;

PFEIFFER, LN ;

WEST, KW .

PHYSICAL REVIEW LETTERS, 1992, 68 (05) :674-677

[8] Topological insulators with inversion symmetry [J].

Fu, Liang ;

Kane, C. L. .

PHYSICAL REVIEW B, 2007, 76 (04)

[9] Surface State Charge Dynamics of a High-Mobility Three-Dimensional Topological Insulator [J].

Hancock, Jason N. ;

van Mechelen, J. L. M. ;

Kuzmenko, Alexey B. ;

van der Marel, Dirk ;

Brune, Christophe ;

Novik, Elena G. ;

Astakhov, Georgy V. ;

Buhmann, Hartmut ;

Molenkamp, Laurens W. .

PHYSICAL REVIEW LETTERS, 2011, 107 (13)

[10] A topological Dirac insulator in a quantum spin Hall phase [J].

Hsieh, D. ;

Qian, D. ;

Wray, L. ;

Xia, Y. ;

Hor, Y. S. ;

Cava, R. J. ;

Hasan, M. Z. .

NATURE, 2008, 452 (7190) :970-U5

← 1 2 →