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arXiv · 1411.1776

Nanostructure Investigations of Nonlinear Differential Conductance in NdNiO$_3$ Thin Films

Will J. Hardy·Heng Ji·Evgeny Mikheev·Susanne Stemmer·Douglas Natelson
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Abstract

Transport measurements on thin films of NdNiO$_3$ reveal a crossover to a regime of pronounced nonlinear conduction below the well-known metal-insulator transition temperature. The evolution of the transport properties at temperatures well below this transition appears consistent with a gradual formation of a gap in the hole-like Fermi surface of this strongly correlated system. As $T$ is decreased below the nominal transition temperature, transport becomes increasily non-Ohmic, with a model of Landau-Zener breakdown becoming most suited for describing $I(V)$ characteristics as the temperature approaches 2~K.

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Will J. Hardy, Heng Ji, Evgeny Mikheev, Susanne Stemmer, Douglas Natelson. 2014-11-06. Nanostructure Investigations of Nonlinear Differential Conductance in NdNiO$_3$ Thin Films. https://doi.org/10.1103/physrevb.90.205117

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