Simulation of the dynamics of the spatial domain structure of a ferroelectric triglycine sulfate crystal

The dynamics of a domain structure of order-disorder ferroelectrics similar to triglycine sulfate is considered. Starting from the Hamiltonian of the problem, a kinetic equation describing the polarization dynamics of ferroelectrics is derived. The results are analyzed and compared with the experimental data.     

Relaxation of the domain structure in triglycine sulfate and deuterated triglycine sulfate crystals in the course of polarization switching

Relaxation of the domain structure in triglycine sulfate and deuterated triglycine sulfate crystals is investigated using polarization switching (during which the domain structure is disturbed from an equilibrium state by a dc electric field) over a wide range of temperatures.     

Polarization switching of triglycine sulfate and deuterated triglycine sulfate single crystals irradiated with a high-current pulsed electron beam

The influence of high-current pulsed electron beams on the processes of polarization switching in triglycine sulfate and deuterated triglycine sulfate single crystals is investigated using the Barkhausen effect.     

Relaxation of the domain structure in doped triglycine sulfate crystals in an internal field

This paper reports on the results of an investigation into the relaxation of the domain structure of triglycine sulfate ferroelectric crystals from a nonequilibrium state induced by rapid cooling of the sample through the phase transition point, in response to an external electric field, and under thermal annealing. The role played by the internal field in the processes of relaxation of the domain structure to the equilibrium state in defect-containing triglycine sulfate crystals is elucidated.     

Temperature dynamics of triglycine sulfate domain structure according to atomic force microscopy and dielectric spectroscopy data

A hydrogen-containing ferroelectric triglycine sulfate (TGS) was comprehensively studied with an atomic force microscopy (AFM) and dielectric spectroscopy. The domain structure dynamics was in situ investigated with piezoresponse force microscopy (PFM) during heating and cooling the TGS crystal near phase transition. Relaxation dependencies of domain boundaries general perimeter and domain dimensions were obtained. TGS dielectric spectra measured at the frequency range from 10 to 10¹¹ Hz were analyzed on basis of significant contribution of conductivity into the dielectric response of ferroelectrics and a good agreement with the experimental data was received. It allows us to obtain more information about temperature dynamics of the domain structure.     

Effect of X-rays on effective nonlinearity of crystals of the triglycine sulfate group

The effect of low irradiation doses on the threshold behavior of the effective permittivity of crystals of the triglycine sulfate group in an ac electric field has been studied. It has been shown that the effect of radiation-induced radicals on the domain structure of the studied crystals is not identical and is controlled by the nature of the previously introduced defects. Interaction energies of domain walls with defects have been calculated.     

The impedance-characteristic method in the study of specific temperature features of dielectric anomaly suppression in triglycine sulfate

The reflection and absorption coefficients in a waveguide loaded on ferroelectric triglycine sulfate (TGS), which has a layered domain structure near the phase transition, are calculated by the impedance-characteristic method. The calculated and experimental data do not reveal any correlations with the specific temperature features in the TGS dielectric response to microwave irradiation. The mechanism of the microwave effect is discussed.     

Dielectric losses in the triglycine sulfate crystal under heating and cooling

Temperature dynamics of the dielectric spectra and domain structure in the triglycine sulfate (TGS) hydrogen-containing ferroelectric under heating and cooling has been studied using the dielectric spectroscopy and atomic-force microscopy methods. The dielectric spectra are analyzed by the temperature-frequency dependences of the losses ε″ and by the temperature behavior of the maximum losses ε″_max in the dispersion region at frequencies ranging from 102 to 106 Hz. A dynamic conductivity model is proposed for calculating temperature dependences of losses ε″_max. The domain structure dynamics during the heating and cooling of the TGS crystal near the phase transition is studied using the in situ piezoresponse force microscopy. It is experimentally and theoretically shown that the relaxation dispersion is governed by the binding of strongly correlated dipoles with the main lattice that serves as a thermostat.     

Effect of the Degree of Overcooling on Relaxation of the Domain Structure of Triglycine Sulphate

Physics of the Solid State - The formation and evolution of the domain structure in the vicinity of the Curie point is studied in triglycine sulfate crystals subjected to fast cooling TC. We derive...     

Mechanoluminescence of ferroelectric crystals

Mechanoluminescence spectra of triglycine sulfate, guanidine aluminium sulfate, rochelle salt, diglycine manganous chloride dihydrate, lithium ammonium tartate monohydrate and potassium dihydrogen phosphate crystals resemble the discharge spectra of nitrogen gases. Glycine silver nitrate, thiourea, ammonium sulfate and azobenzene crystals, the structure of which is centrosymmetric at room temperature, do not show mechanoluminescence. Following the role of crystal structure, the mechanoluminescence excitation is discussed on the basis of the piezo-electrification of the new surfaces created during fracture of the crystals.     

Effect of confined geometry on linear and nonlinear dielectric properties of triglycine sulfate near the phase transition

The temperature dependence of the linear permittivity and the third harmonic generation amplitude of nanocomposites representing nanoporous silica matrices (opal matrix and SBA-15) with triglycine sulfate embedded in pores has been studied in the region of the ferroelectric phase transition. A broadening of the phase transition and an increase its temperature in comparison with bulk triglycine sulfate have been revealed. The latter becomes more significant as the pore size decreases. It has been shown that the nonlinear dielectric properties of nanocomposites near the phase transition differ significantly from the properties of bulk triglycine sulfate.     

Stability of the single-domain state in single crystals of triglycine sulphate

The stability of the single-domain state in single crystals of triglycine sulfate is investigated using the Barkhausen effect. Barkhausen jumps are detected upon invariable macroscopic polarization. The parameters of the observed Barkhausen jumps are estimated and compared.     

Influence of the humidity on dielectric characteristics of porous aluminum oxide with inclusions of triglycine sulfate

The temperature dependences of the capacitance and conductance measured for samples of porous aluminum oxide films with inclusions of triglycine sulfate have been investigated. The character of these dependences obtained for the films treated in a humid atmosphere differs from that of the corresponding dependences measured for the initial porous Al₂O₃ matrix, bulk triglycine sulfate, and dried Al₂O₃ + triglycine sulfate composite. The observed changes are determined by the influence of the water adsorbed on the surface of the film and the water structured in pores of the composite.     

Relaxation of piezobirefringence in triglycine sulfate crystals

The effect of photoelastic relaxation is investigated using triglycine sulfate ferroelectric crystals as an example. The optical and deformation contributions to the photoelastic relaxation are described, and their percentage in the combined effect is determined. Consideration is given to the temperature dependences of the relaxation amplitudes of the path difference and birefringence, which are induced by mechanical stress.     

The influence of low x-ray doses on the properties of chromium-doped triglycine sulfate

The influence of low x-ray doses on pulsed polarization switching in triglycine sulfate crystals at different chromium impurity concentrations is investigated. It is demonstrated that the activation field α in the temperature range 20.0°C-T _c ambiguously depends on the radiation dose for pulses of switching currents of different polarities. It is found that the unipolarity associated with the presence of chromium ions in impurity triglycine sulfate crystals decreases as a result of the interaction between radiation-induced and impurity defects.     

Relaxation stimulated in the domain structure of a triglycine sulfate crystal by an alternating-current electric field

The relaxation of the domain structure in a triglycine sulfate crystal from a nonequilibrium state induced by an alternating-current electric field has been investigated. The distributions of the activation energy of the processes under consideration and the energy of interaction of domain walls with defects over the exciting fields have been obtained.     

Magnetic memory effects in triglycine sulfate ferroelectric crystals

The effect of a magnetic field on the processes of relaxation of the defect structure relaxation in a triglycine sulfate (TGS) ferroelectric (nonmagnetic) crystal has been observed for the first time. The atomic-force microscopy study has shown that the application of a static weak magnetic field (2 T, 20 min) significantly changes the size distribution of defect nanoclusters characteristic of TGS. Previously known macroscopic aftereffects of the magnetic field in TGS (slow relaxation of the dielectric susceptibility, symmetrization of P–E dielectric hysteresis loops, etc.) can be explained by the redistribution of pinning centers of domain walls caused by the magnetically induced reconfiguration of the defect structure.     

Dispersion of Dielectric Permittivity in a Nanocrystalline Cellulose–Triglycine Sulfate Composite at Low and Ultralow Frequencies

Physics of the Solid State - The dispersion of dielectric permittivity in nanocrystalline cellulose–triglycine sulfate composites is studied in the range of frequencies from 10–3 to 106...     

Chaotic behavior of triglycine sulfate crystals containing radiation defects

The temperature-amplitude region of existence of chaotic oscillations in a resonant circuit containing a triglycine sulfate crystal shifts toward higher amplitudes of the repolarization field when the crystal is irradiated with small x-ray doses. This trend is attributed to a change in the kinetics of the domain structure of the crystal in a strong electric field in the presence of radiation defects. Fiz. Tverd. Tela (St. Petersburg) 40, 716–718 (April 1998)     

Change in dielectric properties of triglycine sulfate in a constant magnetic field

The effect of a constant magnetic field on the dielectric properties of triglycine sulfate crystals has been investigated. It has been shown that, after the magnetic treatment of the crystal (2 T, 20 min), the hysteresis loop becomes narrower; i.e., the coercive field decreases, and the dielectric permittivity changes in the region of the phase transition. It has been found that the observed effect is anisotropic with respect to the orientation of the crystal in a magnetic field and occurs when the vector of magnetic induction is perpendicular to the polar axis of the crystal. The relative orientation of the magnetic field and the domain structure determines its sign. The doping of the crystal with chromium makes the effect more pronounced and leads to a change in the kinetics of the magnetically stimulated increase in the dielectric permittivity.