Observation of a uniform temperature dependence in the electrical resistance across the structural phase transition in thin film vanadium oxide ($V{O}_2$)

An electrical study of thin $V{O}_2$ films in the vicinity of the structural phase transition at ${68}^{0}C$ shows (a) that the electrical resistance $R$ follows $log(R)$ $\propto$ $-T$ over the $T$-range, $20<T<{80}^{0}C$ covering both sides of the structural transition, and (b) a history dependent hysteresis loop in $R$ upon thermal cycling. These features are attributed here to transport through a granular network.