Dielectric measurements of nanocrystalline VO$_2$ : Fe films

Dielectric spectroscopy methods revealed the existence of two types of relaxation processes in the semiconductor phase of VO$_2$ : Fe films. The characteristic relaxation times are denoted by $\tau_1$ and $\tau_2$. It is shown that the temperature dependences of $\tau_1$ and $\tau_2$ have hysteresis, the position of the loops of which coincides with the points of the semiconductor-metal phase transition. in VO$_2$ : Fe films. $\tau_1$ corresponds to undoped, and $\tau_2$ corresponds to Fe-doped nanocrystallites of the VO$_2$ film. It is shown that the physical mechanism of the relaxation process is due to the establishment of equilibrium after the action of an electric field on conduction electrons. The numerical values of the parameters of the distribution of relaxers over relaxation times are determined.