High temperature interface superconductivity

Using atomic-layer molecular beam epitaxy we synthesize cuprate bilayers which show interface superconductivity. The superconducting critical temperature (Tc) in the bilayers structures depends on the deposition sequence: Tc=15 K in insulator-metal bilayers, while Tc=36 K in metal-insulator hetero-structures. In this talk I present a comprehensive study of the high-temperature interface superconductivity, including transport measurements, crystal structure determination, and quantitative evaluation of Sr-La intermixing and of redistribution of mobile carriers across the interface. By a new technique, delta-doping tomography using isovalent Zn markers, we have demonstrated that in these heterostructures high-Tc superconductivity occurs within a single CuO2 plane.