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.
@article{arxiv.1310.1001,
title = {Evolution of the fermi surface of a doped topological insulator with carrier concentration},
author = {E. Lahoud and E. Maniv and M. Petrushevsky and M. Naamneh and A. Ribak and S. Wiedmann and L. Petaccia and K. B. Chashka and Y. Dagan and A. Kanigel},
journal= {arXiv preprint arXiv:1310.1001},
year = {2014}
}