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arXiv · 2003.08506

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

Danfeng Li·Bai Yang Wang·Kyuho Lee·Shannon P. Harvey·Motoki Osada·Berit H. Goodge·Lena F. Kourkoutis·Harold Y. Hwang
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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.

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Danfeng Li, Bai Yang Wang, Kyuho Lee, Shannon P. Harvey, Motoki Osada, Berit H. Goodge, Lena F. Kourkoutis, Harold Y. Hwang. 2020-06-23. Superconducting Dome in Nd$_{1-x}$Sr$_x$NiO$_2$ Infinite Layer Films. https://doi.org/10.1103/physrevlett.125.027001

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