Study on vanadium dioxide properties in millimeter wavelength region at metal-semiconductor phase transition

Properties of vanadium dioxide films are investigated in the millimetre range of wavelengths at a metal-semiconductor phase transformation. Reflection and transmission of radiation have been measured in the range of wavelengths 0.8-4.2 mm with the temperature varying from 25 deg to 75 deg C. By the experimentally obtained coefficients of reflection and transmission the complex dielectric constant, indices of refraction and absorption, and high-frequency conductivity are determined. The results obtained from the SHF measurements are compared with those made with a constant current. It has been concluded that electrodynamic properties of material can be described by classical dispersion relations in the range from 0.8 to 4.2 mm