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تسجيل مستخدم جديدEvidence for a capacitor network near the metal insulator transition in VO2 thin films probed by in-plane impedance spectroscopy
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Impedance spectroscopy measurements were performed in high quality Vanadium dioxide (VO2) thin films. This technique allows us investigate the resistive and capacitive contribution to the dielectric response near the metal-insulator transition (MIT). A non ideal RC behavior was found in our films from room temperature up to 334 K. A decrease of the total capacitance was found in this region, possibly due to interface effects. Above the MIT, the system behaves like a metal as expected, and a modified equivalent circuit is necessary to describe the impedance data adequately. Around the MIT, an increase of the total capacitance is observed.
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