Topological superconductivity is an exotic phase of matter in which the fully gapped superconducting bulk hosts gapless Majorana surface states protected by topology. Intercalation of copper, strontium or niobium between the quintuple layers of the topological insulator Bi2Se3 increases the carrier density and leads to superconductivity that is suggested to be topological. Here we study the electronic structure of strontium-intercalated Bi2Se3 using angle resolved photoemission spectroscopy (ARPES) and Shubnikov-de Haas (SdH) oscillations. Despite the apparent low Hall number of ∼2×1019cm−3, we show that the Fermi surface is shaped as an open cylinder with a larger carrier density of ∼1020cm−3. We suggest that superconductivity in intercalated Bi2Se3 emerges with the appearance of a quasi-2D open Fermi surface.
@article{arxiv.2012.06868,
title = {Link between superconductivity and a Lifshitz transition in intercalated Bi$_2$Se$_3$},
author = {A. Almoalem and I. Silber and S. Sandik and M. Lotem and A. Ribak and Y. Nitzav and A. Yu. Kuntsevich and O. A. Sobolevskiy and Yu. G. Selivanov and V. A. Prudkoglyad and M. Shi and L. Petaccia and M. Goldstein and Y. Dagan and A. Kanigel},
journal= {arXiv preprint arXiv:2012.06868},
year = {2021}
}