Superconductivity at the interface of a heterostructure confined to nanometer-sized scale offers unique opportunities to study the exotic physics of two-dimensional superconductivity. The realization of superconductivity at the interface between a topological insulator and an iron-chalcogenide compound is highly attractive for exploring several recent theoretical predictions involving these two new classes of materials. Here, we report transport measurements on a Bi2Te3/FeTe heterostructure fabricated via van der Waals epitaxy, which demonstrate superconductivity at the interface induced by the Bi2Te3 epilayer with thickness even down to one quintuple layer. The two-dimensional nature of the observed superconductivity with the highest transition temperature around 12 K was verified by the existence of a Berezinsky-Kosterlitz-Thouless transition and the diverging ratio of in-plane to out-plane upper critical field on approaching the superconducting transition temperature. With the combination of interface superconductivity and Dirac surface states of Bi2Te3, the heterostructure studied in this work provides a novel platform for realizing Majorana fermions.
@article{arxiv.1309.6040,
title = {Two-dimensional superconductivity at the interface of a Bi2Te3/FeTe heterostructure},
author = {Qing Lin He and Hongchao Liu and Mingquan He and Ying Hoi Lai and Hongtao He and Gan Wang and Kam Tuen Law and Rolf Lortz and Jiannong Wang and Iam Keong Sou},
journal= {arXiv preprint arXiv:1309.6040},
year = {2015}
}