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arXiv · 1504.01270

Observation of Two-Dimensional Bulk Electronic States in a Superconducting Topological Insulator Heterostructure Cux(PbSe)5(Bi2Se3)6: Implications for Unconventional Superconductivity

K. Nakayama·H. Kimizuka·Y. Tanaka·T. Sato·S. Souma·T. Takahashi·Satoshi Sasaki·Kouji Segawa·Yoichi Ando
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Abstract

We have performed angle-resolved photoemission spectroscopy (ARPES) on Cux(PbSe)5(Bi2Se3)6 (CPSBS; x = 1.47), a superconductor derived from a topological insulator heterostructure, to elucidate the electronic states relevant to the occurrence of possible unconventional superconductivity. Upon Cu intercalation into the parent compound (PbSe)5(Bi2Se3)6, we observed a distinct energy shift of the bulk conduction band due to electron doping. Photon-energy dependent ARPES measurements of CPSBS revealed that the observed bulk band forms a cylindrical electronlike Fermi surface at the Brillouin-zone center. The two-dimensional nature of the bulk electronic states suggests the occurrence of odd-parity Eu pairing or even-parity d-wave pairing, both of which may provide a platform of Majorana bound states in the superconducting state.

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K. Nakayama, H. Kimizuka, Y. Tanaka, T. Sato, S. Souma, T. Takahashi, Satoshi Sasaki, Kouji Segawa, Yoichi Ando. 2015-04-06. Observation of Two-Dimensional Bulk Electronic States in a Superconducting Topological Insulator Heterostructure Cux(PbSe)5(Bi2Se3)6: Implications for Unconventional Superconductivity. https://doi.org/10.1103/physrevb.92.100508

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