Effects of substrate temperature on the unusual non-Fermi liquid metal to insulator transition in perovskite SrIrO3 thin films

Electronic transport has been investigated for strong spin-orbit coupled perovskite SrIrO3 thin films grown at various substrate temperatures. The electronic transport of the SrIrO3 films is found to be very sensitive to the growth parameters; in particular, the film can either be a metal or an insulator depending upon the substrate growth temperature. While all the metallic films show unusual sublinear temperature dependent non-Fermi liquid behaviors in resistivity, the insulating film grown at a higher temperature stands out for its inhomogeneous Ir distribution, as analyzed by secondary ion mass spectrometry. This observation demonstrates that the inhomogeneous distribution of cations can be one of the fundamental factors in affecting the electronic transport in heavy element based oxide films and heterostructures.