Observation of Time-Reversal-Protected Single-Dirac-Cone Topological-Insulator States in Bi2Te3 and Sb2Te3
We show that the strongly spin-orbit coupled materials Bi2Te3 and Sb2Te3 and their derivatives belong to the Z2 topological-insulator class. Using a combination of first-principles theoretical calculations and photoemission spectroscopy, we directly show that Bi2Te3 is a large spin-orbit-induced indirect bulk band gap (δ~150meV) semiconductor whose surface is characterized by a single topological spin-Dirac cone. The electronic structure of self-doped Sb2Te3 exhibits similar Z2 topological properties. We demonstrate that the dynamics of spin-Dirac fermions can be controlled through systematic Mn doping, making these materials classes potentially suitable for topological device applications.
D. Hsieh and Y. Xia and X. Dong and L. A. Wray and F. Meier and J. H. Dil and J. Osterwalder and L. Patthey and A. V. Fedorov and H. Lin and A. Bansil and D. C. Grauer and Y. S. Hor and R. J. Cava and M. Z. Hasan, "Observation of Time-Reversal-Protected Single-Dirac-Cone Topological-Insulator States in Bi2Te3 and Sb2Te3," Physical Review Letters, vol. 103, no. 14, American Physical Society (APS), Sep 2009.
The definitive version is available at http://dx.doi.org/10.1103/PhysRevLett.103.146401
Keywords and Phrases
Band Gaps; Device Application; Dirac Fermions; First-principles; Large Spin; Materials Class; Mn-doping; Photoemission Spectroscopy; Self-doped; Spin Orbits; Theoretical Calculations; Time-reversal; Topological Properties; Doping (Additives); Electronic Structure; Emission Spectroscopy; Manganese; Manganese Compounds; Sound Reproduction; Spin Dynamics
International Standard Serial Number (ISSN)
Article - Journal
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