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arXiv · 1310.1001

Evolution of the fermi surface of a doped topological insulator with carrier concentration

E. Lahoud·E. Maniv·M. Petrushevsky·M. Naamneh·A. Ribak·S. Wiedmann·L. Petaccia·K. B. Chashka·Y. Dagan·A. Kanigel
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Abstract

In an ideal bulk topological-insulator (TI) conducting surface states protected by time reversal symmetry enfold an insulating crystal. However, the archetypical TI, Bi2Se3, is actually never insulating; it is in fact a relatively good metal. Nevertheless, it is the most studied system among all the TIs, mainly due to its simple band-structure and large spin-orbit gap. Recently it was shown that copper intercalated Bi2Se3 becomes superconducting and it was suggested as a realization of a topological superconductor (TSC). Here we use a combination of techniques that are sensitive to the shape of the Fermi surface (FS): the Shubnikov-de Haas (SdH) effect and angle resolved photoemission spectroscopy (ARPES) to study the evolution of the FS shape with carrier concentration, n. We find that as n increases, the FS becomes 2D-like. These results are of crucial importance for understanding the superconducting properties of CuxBi2Se3.

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E. Lahoud, E. Maniv, M. Petrushevsky, M. Naamneh, A. Ribak, S. Wiedmann, L. Petaccia, K. B. Chashka, Y. Dagan, A. Kanigel. 2013-10-10. Evolution of the fermi surface of a doped topological insulator with carrier concentration. https://doi.org/10.1103/physrevb.88.195107

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