Interface-enhanced superconductivity of single layer FeSe grown on non-TiO2 based oxides*

The single layer FeSe film on SrTiO₃ indicates that interfaces can play a significant role in high-temperature superconductivity. Here we report a new FeSe-based interface, single layer FeSe grown on non-TiO₂ based oxides by molecular beam epitaxy (MBE) method, was successfully obtained. The structure of the interface was determined by high resolution transmission electron microscopy (HRTEM). The angle-resolved photoemission spectroscopy (ARPES) shows that it is superconducting with a large gap, while the ex-situ mutual inductance measurements indicate it has a high onset temperature for diamagnetism. This heterostructure can provide a new platform for understanding the interface-enhanced superconductivity.