V. N. Derkach

Dielectric losses in diamond-like materials at the cryogenic temperatures in the millimeter waveband

The paper presents the study results of the temperature dependence of the dielectric loss at millimeter waves in the temperature range of 1.0 - 300 K in some low-absorbing dielectric and semiconductor materials having the diamond-like crystal lattices. It is shown that the absorption maxima at helium temperatures in materials with a centrosymmetric lattice are primary associated with both intrinsic and extrinsic losses, and in materials with a noncentrosymmetric lattice - with extrinsic losses. The relaxation times, activation energies and other parameters characterizing the Debye mechanism of extrinsic losses of the investigated materials are determined on the base of the approximation model of temperature dispersion of losses.

Investigation of the Low-Loss Dielectric Materials in the Wide Temperature Range

The operational regimes of cryodielectrometer designed for measurement the dielectric parameters of materials with small dissipation in millimeter waveband is described. Dependences of loss tangent on temperature for some dielectric and semiconductor materials in frequency band 40-80 GHz and temperature range 0.85-300 K are analyzed