| Summary: | Functional oxides with strongly correlated electron systems, such as vanadium dioxide, manganite, and so on, show a metal-insulator transition and an insulator-metal transition (MIT and IMT) with a change in conductivity of several orders of magnitude. Since the discovery of phase separation during transition processes, many researchers have been trying to capture a nanoscale electronic domain and investigate its exotic properties. To understand the exotic properties of the nanoscale electronic domain, we studied the MIT and IMT properties for the VO<sub>2</sub> electronic domains confined into a 20 nm length scale. The confined domains in VO<sub>2</sub> exhibited an intrinsic first-order MIT and IMT with an unusually steep single-step change in the temperature dependent resistivity (<i>R</i>-<i>T</i>) curve. The investigation of the temperature-sweep-rate dependent MIT and IMT properties revealed the statistical transition behavior among the domains. These results are the first demonstration approaching the transition dynamics: the competition between the phase-transition kinetics and experimental temperature-sweep-rate in a nano scale. We proposed a statistical transition model to describe the correlation between the domain behavior and the observable <i>R</i>-<i>T</i> curve, which connect the progression of the MIT and IMT from the macroscopic to microscopic viewpoints.
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