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arXiv · 0812.2078

Electrons on the surface of Bi2Se3 form a topologically-ordered two dimensional gas with a non-trivial Berry's phase

Y. Xia·L. Wray·D. Qian·D. Hsieh·A. Pal·H. Lin·A. Bansil·D. Grauer·Y. S. Hor·R. J. Cava·M. Z. Hasan
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Abstract

The interface between a superconductor and a topological insulator has been proposed to harbor novel quasiparticles that realize physical schemes for fault-tolerant quantum computation. Here, we present high resolution angle-resolved photoemission experimental results, which along with first principles calculations, suggest that the surface-edge states of Bi2Se3 form a topological 2D metal. When magnetic atoms are deposited, the surface tends to lose Kramers' degeneracy and a k-space connection thread between the bulk valence and conduction bands is lost. Our observed states carry a πBerry's phase suggesting that although the real materials are often electron doped fully undoped Bi2Se3 would be a Z2 topological insulator at room temperature.

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Y. Xia, L. Wray, D. Qian, D. Hsieh, A. Pal, H. Lin, A. Bansil, D. Grauer, Y. S. Hor, R. J. Cava, M. Z. Hasan. 2008-12-11. Electrons on the surface of Bi2Se3 form a topologically-ordered two dimensional gas with a non-trivial Berry's phase. https://arxiv.org/abs/0812.2078

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