Superconducting Dome in Nd1-xSrxNiO2 Infinite Layer Films

We report the phase diagram of Nd1-xSrxNiO2 infinite layer thin films grown on SrTiO3. A superconducting dome spanning 0.125 < x < 0.25 is found, remarkably similar to cuprates, albeit over a narrower doping window. However, while cuprate superconductivity is bounded by an insulator for underdoping and a metal for overdoping, here we observe weakly insulating behavior on either side of the dome. Furthermore, the normal state Hall coefficient is always small and proximate to a continuous zero crossing in doping and in temperature, in contrast to the ~1/x dependence observed for cuprates. This suggests the presence of both electronand hole-like bands, consistent with band structure calculations.