First principles predictions of superconductivity in doped stanene

Stanene, composed of tin atoms arranged in a single layer, is the tin analogue of graphene and past studies predicted it to be a topological insulator. An energy band gap (of similar to 0.1 eV) was obtained in previous calculations for the buckled honeycomb structure of stanene and, thus, phonon-mediated superconductivity in this material is ruled out. In this work we investigated, from first principles calculations within density functional theory (DFT), the possibility of producing phonon-mediated superconductivity in stanene by doping the material. It was found that doping with calcium (lithium) leads to superconductivity, albeit, with a very low superconducting transition temperature T-c of similar to 1.3 K (similar to 1.4 K), lower than the value (3.7 K) for bulk beta-Tin. (C) 2016 Elsevier B.V. All rights reserved.