English
Related papers

Related papers: Surface-state spin textures in strained bulk HgTe:…

200 papers

We investigated the magnetotransport properties of strained, 80nm thick HgTe layers featuring a high mobility of mu =4x10^5 cm^2/Vs. By means of a top gate the Fermi-energy is tuned from the valence band through the Dirac type surface…

Mesoscale and Nanoscale Physics · Physics 2015-06-16 D. A. Kozlov , Z. D. Kvon , D. Weiss , E. B. Olshanetsky , N. N. Mikhailov , S. A. Dvoretsky

Topological insulators are a new class of insulators in which a bulk gap for electronic excitations is generated by strong spin orbit coupling. These novel materials are distinguished from ordinary insulators by the presence of gapless…

Three dimensional topological insulator crystals consist of an insulating bulk enclosed by metallic surfaces, and detailed theoretical predictions about the surface state band topology and spin texture are available. While several…

We study the topologically non-trivial semi-metals by means of the 6-band Kane model. Existence of surface states is explicitly demonstrated by calculating the LDOS on the material surface. In the strain free condition, surface states are…

Mesoscale and Nanoscale Physics · Physics 2011-04-14 Rui-Lin Chu , Wen-Yu Shan , Jie Lu , Shun-Qing Shen

We investigate the band dispersion and the spin texture of topologically protected surface states in the bulk topological insulators Bi2Se3 and Bi2Te3 by first-principles methods. Strong spin-orbit entanglement in these materials reduces…

Mesoscale and Nanoscale Physics · Physics 2015-03-17 Oleg V. Yazyev , Joel E. Moore , Steven G. Louie

We report on microscopic tight-binding modeling of surface states in Bi$_2$Se$_3$ three-dimensional topological insulator, based on a sp$^3$ Slater-Koster Hamiltonian, with parameters calculated from density functional theory. The effect of…

Mesoscale and Nanoscale Physics · Physics 2014-11-04 A. Pertsova , C. M. Canali

We present a magneto-optical study of the three-dimensional topological insulator, strained HgTe using a technique which capitalizes on advantages of time-domain spectroscopy to amplify the signal from the surface states. This measurement…

Topological insulators represent a new quantum state of matter that are insulating in the bulk but metallic on the edge or surface. In the Dirac surface state, it is well-established that the electron spin is locked with the crystal…

Topological insulators in the Bi$_2$Se$_3$ family manifest helical Dirac surface states that span the topologically ordered bulk band gap. Recent scanning tunneling microscopy measurements have discovered additional states in the bulk band…

Materials Science · Physics 2018-08-01 Yishuai Xu , Guodong Jiang , Janet Chiu , Lin Miao , Erica Kotta , Yutan Zhang , Rudro R. Biswas , L. Andrew Wray

Bulk Bi2Te3 is known to be a topological insulator. We investigate surface states of Bi2Te3(111) thin films using density-functional theory including spin-orbit coupling. We construct a method to unambiguously identify surface states of…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 Kyungwha Park , J. J. Heremans , V. W. Scarola , Djordje Minic

The quantum spin Hall (QSH) effect is the property of a new state of matter which preserves time-reversal, has an energy gap in the bulk, but has topologically robust gapless states at the edge. Recently, it has been shown that HgTe quantum…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Xi Dai , Taylor L. Hughes , Xiao-Liang Qi , Zhong Fang , Shou-Cheng Zhang

We present a theory of electronic properties of HgTe quantum dot and propose a strain sensor based on a strain-driven transition from a HgTe quantum dot with inverted bandstructure and robust topologically protected quantum edge states to a…

Mesoscale and Nanoscale Physics · Physics 2014-05-12 Marek Korkusinski , Pawel Hawrylak

We introduce a dinstint approach to engineer a topologically protected surface state of a topological insulator. By covering the surface of a topological insulator, Bi2Te2Se, with a Bi monolayer film, the original surface state is…

We report a detailed experimental study of the band structure of the recently discovered topological material $\textrm{Hf}_{2}\textrm{Te}_2\textrm{P}$. Using the combination of scanning tunneling spectroscopy and angle-resolved…

Mesoscale and Nanoscale Physics · Physics 2019-08-21 T. J. Boyle , A. Rossi , M. Walker , P. Carlson , M. K. Miller , J. Zhao , P. Klavins , C. Jozwiak , A. Bostwick , E. Rotenberg , V. Taufour , I. Vishik , E. H. da Silva Neto

The characteristics of topological insulators are manifested in both their surface and bulk properties, but the latter remain to be explored. Here we report bulk signatures of pressure-induced band inversion and topological phase…

The topology of a topological material can be encoded in its surface states. These surface states can only be removed by a bulk topological quantum phase transition into a trivial phase. Here we use photoemission spectroscopy to image the…

The phase transition from a topological insulator to a trivial band insulator is studied by angle-resoled photoemission spectroscopy on Bi$_{2-x}$In$_{x}$Se$_{3}$ single crystals. We first report the complete evolution of the bulk band…

Strained bulk HgTe is a three-dimensional topological insulator, whose surface electrons have a high mobility (30,000 cm^2/Vs), while its bulk is effectively free of mobile charge carriers. These properties enable a study of transport…

Using ab initio electronic structure calculations we investigate the change of the band structure and the nu_0 topological invariant in HgSe (non-centrosymmetric system) under two different type of uniaxial strain along the [001] and [110]…

Materials Science · Physics 2015-06-15 Lars Winterfeld , Luis A. Agapito , Jin Li , Nicholas Kioussis , Peter Blaha , Yong P. Chen

The band inversions that generate the topologically non-trivial band gaps of topological insulators and the isolated Dirac touching points of three-dimensional Dirac semimetals generally arise from the crossings of electronic states derived…