Research on superconductors and topological insulators composed of one or a few atomic layers has been booming for decades, expecting new quantum phenomena beyond those in three-dimensional crystals. This research trend has appeared by merging research fields of graphene, transition metal dichalcogenide, strong spin-orbit coupling materials on one side, and surface/interface physics and epitaxial growth technology on another side. A large part of such research activity is originated from China.  

In my talk, I would like to show some examples of research in my group, such as superconducting bilayer graphene with metal intercalation, unconventional superconductivity in single-atomic-layers grown on semiconductor surfaces, and controlling of symmetry in topological surface states. Our specialty in experiments is in-situ transport measurement techniques such as four-tip scanning tunneling microscope in ultrahigh vacuum, which enables to unveil the intrinsic charge/spin transport properties of air-sensitive atomic layers.