Rectifying NdNiO_3/Nb:SrTiO_3 junctions as a probe of the surface electronic structure of NdNiO_3

摘要

We have studied the electronic properties of junctions formed between Nb-doped SrTiO_3 substrates, an n-type semiconductor, and NdNiO_3 films, which exhibit a strong first-order phase transition from a high temperature paramagnetic metal to a low temperature antiferromagnetic insulator. Although the junctions are rectifying at all temperatures, the current-voltage and capacitance characteristics show no indication of the metal-insulator transition clearly observed in the films. This suggests that the surface electronic structure of NdNiO_3 is distinct from the interior of the film and does not undergo the bulk transition.