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arXiv · 1401.4129

Separating electric field and thermal effects across the metal-insulator transition in vanadium oxide nanobeams

Adam A. Stabile·Sujay K. Singh·Tai-lung Wu·Luisa Whittaker·Sarbajit Banerjee·G. Sambandamurthy
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Abstract

We present results from an experimental study of the equilibrium and non-equilibrium transport properties of vanadium oxide nanobeams near the metal-insulator transition (MIT). Application of a large electric field in the insulating phase across the nanobeams produces an abrupt MIT and the individual roles of thermal and non-thermal effects in driving the transition are studied. Transport measurements at temperatures ($T$) far below the critical temperature ($T_c$) of MIT, in several nanoscale vanadium oxide devices, show that both $T$ and electric field play distinctly separate, but critical roles in inducing the MIT. Specifically, at $T << T_c$ electric field dominates the MIT through an avalanche-type process, whereas thermal effects become progressively critical as $T$ approaches $T_c$.

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Adam A. Stabile, Sujay K. Singh, Tai-lung Wu, Luisa Whittaker, Sarbajit Banerjee, G. Sambandamurthy. 2014-01-16. Separating electric field and thermal effects across the metal-insulator transition in vanadium oxide nanobeams. https://doi.org/10.1063/1.4926334

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