Proximity-induced superconductivity in SnTe thin films

Superconducting topological crystalline insulators (TCIs) are theorized to host new types of topologically protected surface states distinct from those at the surface of superconducting Z₂ topological insulators (TIs). While superconducting proximity effect has been widely used to induce superconductivity in Z₂ TIs, the efforts to induce superconductivity in TCIs have been hindered by growth difficulties. Here we report the synthesis of heterostructures of a prototypical TCI SnTe(111) and high temperature superconductor Fe(Te,Se) using molecular beam epitaxy. Utilizing low-temperature scanning tunneling microscopy and spectroscopy as function of temperature and magnetic field, we show strong evidence of induced superconductivity at the surface of SnTe. Our work provides a new platform for studying emergent phenomena in superconducting TCIs.