ARPES Study on Layer-Dependent Electronic Structure of FeSe/SrTiO3 Films

the recent discover of high-Tc superconductivity in a single-layer FeSe/SrTiO3 film has attracted much attention.. Our previous ARPES studies on the FeSe/SrTiO3 films have observeddistinct electronic structure of the single-layer FeSe/SrTiO3 film, established a phase diagram and observed a signature of high Tc over 65K in the annealed single-layer FeSe/SrTiO3 films, revealed thedichotomy of electronic structure and superconductivity between the single-layer and double-layer FeSe/SrTiO3 films, and observed an insulator-superconductor transition in the single-layer FeSe/SrTiO3 films. In this talk, we will present our new ARPES results on the FeSe/SrTiO3 films with many different layers, from single-layer up to 50-layers. This systematic study will provide insight in understanding the evolution of electronic structure and superconductivity from the single-layer FeSe film, to multiple-layer FeSe film and eventually to the bulk FeSe superconductor.