Capacitive network near the metal insulator transition in Vanadium Dioxide

ORAL

Abstract

Recent infrared spectroscopy and transport measurements in nano-scaled junction of VO2 have revealed the existence of phase separation into metallic and insulating phases. Here we present Impedance spectroscopy measurements performed in high quality Vanadium dioxide (VO$_2$) thin films for the first time. This technique allows distinguishing between the resistive and capacitive response of the VO$_2$ films and provides the dielectric properties across the metal-insulator transition (MIT). The film capacitance exhibits an unusual increase close to the MIT which implies the formation of a capacitor network produced by the nanoscale phase separation of metallic and insulating phases. This work has been supported by AFOSR, COLCIENCIAS, CENM and Ramon y Cajal Fellowship.

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Authors

  • J.G. Ramirez

    Universidad de los Andes

  • E.J. Patino

    Universidad de los Andes

  • R. Schmidt

    Universidad Complutense de Madrid

  • A. Sharoni

    Bar-Ilan University

  • M.E. Gomez

    Physics Department Universidad del Valle Cali, Colombia, Universidad del Valle

  • I.K. Schuller

    Department of Physics and Center for Advanced Nanotechnology, University of California San Diego, La Jolla, California 92093, University of California, San Diego, Department of Physics and Center for Advanced Nanoscience, University of California San Diego, La Jolla CA 92093, University of California-San Diego