Universal installation for studying structural defects in electrical and optical fiber materials

Abstract

A universal device for experimentally studying the migration of microscopic structure defects and the features of dielectric relaxation is proposed. it allows using the thermo stimulated depolarization method, in combination with the measurement of the tangent of the angle of dielectric losses and the thermo stimulated polarization current, to perform dielectric spectroscopy of hydrogen-bonded crystals and perform analysis of the properties and parameters of structure defects. A smaller (in comparison with the existing installation) additional compact device for measuring small values of electrical capacitance and the tangent of the angle of dielectric losses, including an electrometer B7-30, was designed, measurement was carried out using a q-factor meter VM 560. When measuringtgδ > 0.1, the VM-507 device was used. An experimental methodology is proposed that allows, in combination with the method of minimizing the comparison function (MFC - method), with a high degree of accuracy, to calculate the molecular characteristics of structural defects in composite materials based on semiconductors and dielectrics used in the electrical and optical fiber industry, electric power and insulation technology.

Theoretical Studies of Nonlinear Relaxation Electrophysical Phenomena in Dielectrics with Ionic–Molecular Chemical Bonds in a Wide Range of Fields and Temperatures

“…The numerical values of the statistically averaged quantum transparency coefficient are significantly dependent on the parameters of the potential barrier (especially from its height, which makes sense of the activation energy), crystal thickness and temperature range. Thus, in [16], it was established that accounting for splits of proton energy levels in the HBC on sublevels (in an unperturbed potential field) with the proton activation energy of 0.01 eV leads to a shift in the temperature maximum of the statistically aver-aged transparency coefficient from 55 K with an amplitude of 0.12 (in the absence of energy spectrum degeneration) to 150 K with an amplitude of 0.14 (in the presence of energy spectrum degeneration). Ref.…”

“…[13][14]. By the method of mathematical induction in the infinite approximation of the perturbation theory at the main frequency ω, the frequency harmonic of polarization P (ω) (𝑡) ( [3], p. 16) was calculated and the nonlinear frequency-temperature spectra of the CDP were constructed and studied in detail ( [1], pp. [43][44][45][46][47][48][49].…”

“…This allows us, with a certain degree of accuracy, to judge the significant influence of the temperature range on the mechanism of the nonlinear relaxation processes when generating polarization of the dielectric in the wide range of field parameters. It is obvious that in the region of weak fields (0.1-1 MV/m) the non-linearities will appear due to low-temperature (10-50 K) polarization effects (quantum diffusion polarization), and in the region of strong fields (10-1000 MV/m) the non-linearities will appear due to high-temperature (550-1500 K) polarization effects (nonlinear bulk-charge polarization of the mixed type) [7,[12][13][14][15][16].…”

“…Another criterion of validity of formulae ( 8) and ( 25) of the nonlinear approximation of the perturbation theory investigated above is their ultimate transition to results of the linear kinetic theory of the relaxation polarization [7,[12][13][14][15][16]. To this end, we simplify the expression for the polarization (8).…”

“…Ref. [14] shows the effects of the thickness of the crystal layer on quantum transparency and dielectric constant of the crystal of the HBC type at nanoscale thicknesses of the sample, when, in layers with a thickness of 10 nm, in the case of the zone structure of the energy spectrum of protons with an activation energy of the proton of 0.01 eV, there is an increase in the amplitude of the quantum transparency coefficient to 0.98-0.99 (proton superconductivity) at a maximum temperature of 10-15 K, and the amplitude of the stationary dielectric permittivity Re ε ^( ) calculated according to formula (61) reaches abnormally high values (2.5-3.0 million) [16]. This indicates the formation of the ferroelectric state in HBC due to quantum tunnel movement of protons in hydrogen sublattice of HBC nanofilms in the region of liquid helium temperatures.…”