Hubbard gap modulation in vanadium dioxide nanoscale tunnel junctions.

Huefner, Magdalena; Ghosh, Ram Krishna; Freeman, Eugene; Shukla, Nikhil; Paik, Hanjong; Schlom, Darrell G; Datta, Suman · Nano Lett · 2014

basic_science · Level V

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Abstract

We locally investigate the electronic transport through individual tunnel junctions containing a 10 nm thin film of vanadium dioxide (VO2) across its thermally induced phase transition. The insulator-to-metal phase transition in the VO2 film collapses the Hubbard gap (experimentally determined to be 0.4 ± 0.07 V), leading to several orders of magnitude change in tunnel conductance. We quantitatively evaluate underlying transport mechanisms via theoretical quantum mechanical transport calculations which show excellent agreement with the experimental results.