Broadband measurements of dielectric characteristics of ice near 0$^\circ$C temperature

The paper presents a technique for ultra-wide-band measurements of dielectric permittivity using the microwave and optical ranges of weakly absorbing inhomogeneous media. Measurements of fresh ice near the phase transition point (at 0$^\circ$C) were performed. The ratio of the extreme values of the probing frequencies used in the experiments is $\sim$ 10$^6$. The recent detection of a new phenomenon has been confirmed – “enlightenment” (an increase in the transmitted radiation power in fresh ice) in the microwave and optical ranges up to tens of percent or more for samples with a thickness of $\sim$ 0.1 m. The greatest effect was observed when the electric field vector was positioned parallel to the base plane of the ice crystals. A mechanism of the phenomenon associated with the occurrence of plasmon resonance on structures appearing in nanometer-thick layers formed during the flow (plastic deformation) of ice is proposed.