Transport properties of NdNiO3 thin films made by pulsed-laser deposition

Pulsed-laser deposition was used to make thin films of NdNiO3 on a variety of substrates. The films were found to be single phase perovskite in all cases. However, the transport behavior varied strongly as a function of the substrate used: the films were semiconducting on MgO, but showed a metal-semiconductor phase transition on SrTiO3 and NdGaO3. The best electrical-switching properties corresponded to films grown on NdGaO3, with the resistivity changing abruptly by more than two orders of magnitude at TMI∼185 K. Very thin films (∼35 nm) were also grown on NdGaO3 substrates to investigate the epitaxial strain effect on the transition. It appears that biaxial tensile strain stabilizes the high temperature metallic phase, thus lowering TMI.