"Phase diagram of infinite layer praseodymium nickelate Pr1-xSrxNiO2 thin films"

Motoki Osada: Bai Yang Wang, Kyuho Lee, Danfeng Li, and Harold Y. Hwang; Physical Review Materials, 12/15/20.

Additional Authors: Bai Yang Wang, Kyuho Lee, Danfeng Li, and Harold Y. Hwang

Abstract:

We report the phase diagram of infinite layer Pr1−xSrxNiO2 thin films synthesized via topotactic reduction from the perovskite precursor phase using CaH2. Based on the electrical transport properties, we find a doping-dependent superconducting dome extending between x=0.12 and 0.28 with a maximum superconducting transition temperature Tc of 14 K at x=0.18, bounded by weakly insulating behavior on both sides. In contrast to the narrower dome observed in Nd1−xSrxNiO2, a local Tc suppression near x=0.2 was not observed for the Pr1−xSrxNiO2 system. Normal-state Hall effect measurements indicate mixed carrier contributions of both electrons and holes and show a sign change in the Hall coefficient as functions of temperature and x, quite similar to that in Nd1−xSrxNiO2. Also similar is the observation of a minimum in the normal-state resistivity associated with the superconducting compositions. These findings indicate an infinite layer nickelate phase diagram that is relatively insensitive to the rare-earth element but suggest that disorder arising from the variations of the ionic radii on the rare-earth site affects the superconducting dome.