Superconducting Dome in Nd${}_{1-x}$Sr${}_x$NiO${}_2$ Infinite Layer Films

Abstract

We report the phase diagram of Nd${}_{1-x}$Sr${}_x$NiO${}_2$ infinite layer thin films grown on SrTiO${}_3$. 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 $\sim 1/x$ dependence observed for cuprates. This suggests the presence of both electron- and hole-like bands, consistent with band structure calculations.

18 pages (including Supplemental Material), 7 figures (including 4 supplemental figure)