Electronic structure of copper-oxide monolayer

Copper-based high temperature superconductors have a common layered structure CuO₂ plane where superconductivity takes place. Therefore, it draws attention that whether superconductivity occurs in a single layer of CuO₂ plane and how the superconductivity in this 2D structure differs from that in bulk cuprate system. To study the superconductivity of the CuO₂ monolayer, we construct a heterostructure system for surface-accessible CuO₂ monolayer. With pulsed laser deposition and angle-resolved photoemission spectroscopy, we synthesized single layer of La_2-xSr_xCuO₄(LSCO) and measured its electronic structure. Monolayer LSCO has metallic electronic structure and bulk-like fermi surface. The hole doping ratio of the monolayer LSCO depends on underlying buffer layer since the monolayer is strongly affected by cation intermixing at the interface. Our work would provide a platform for researching 2D cuprate superconductivity.