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Using an ultrahigh-frequency, noncontact resonator method, the Influence of an electric field on the conductivity and the minority carrier lifetime in p-type InSb at 80‡K was studied. The conductivity of p-type InSb increased with increasing electric field; this effect was attributed to an increase in the carrier concentration as a result of impact (shock) iontzation, while the change taking place in the minority carrier lifetime was attributed to charge exchange in the recombination centers.

Variations of dielectric-characteristic spatial distributions in space and time are studied in dielectric media with capillary-porous structure (e.g., soils, certain construction materials) with a view to improving the reliability and accuracy of radio-frequency subsurface diagnosis of their states and properties. It is shown that for real climatic temperature and humidity effects, these variations are nonstationary in nature and can be found with accuracy satisfactory for practical purposes by solving the corresponding temperature-moisture problem with power-law descriptions of the dielectric characteristics of these media as functions of the concentration of free water with correction for the frequency—temperature scatter of its dielectric properties.

The dependence of the electrical conductivity and dielectrical permeability for dispersion mixtures of a dielectric and a conductor (moist top) on the composition and properties of the components have been studied in the frequency range 0 to 107 Hz. It is shown that for the moisture content, which allows one to model the soil by the two-phase air -water system, the obtained dependences are satisfactorily described by the equations of the percolation theory.

The influence of heat and moisture factors on the spatial distribution of dielectric characteristics in capillary-porous media with a conductive component is investigated using saline topsoils as an example. It is shown that the spatial distributions and absolute values of the dielectric characteristics of such media depend strongly on the concentration and salinity of the liquid component. It is found that the results must be used for properly conditioned interpretation of radio-wavelength sensing to determine the ecological state of the underlying surface.

These experimental results have shown that when an shf electric field is applied to a small semiconducting sample there is a redistribution of free carriers in the sample, which results in an increase in the carrier concentration near the sample boundaries and a decrease in the center. Carrier trapping at the sample surface has a pronounced effect on this redistribution.