Dielectric anomalies and phase transition in glycinium phosphite crystal under the influence of a transverse electric field

et al. 2009

Modified four-sublattice model for Rochelle salt by taking into account piezoelectric interactions with shear strain ε 4 , ε 5 and ε 6 is proposed. Components of polarization vector and static dielectric permittivity tensor for both mechanically clamped and free crystals, their piezoelectric characteristics and elastic modules are derived in the mean field approximation. A comprehensive study of transverse field effect on phase transition temperatures, dielectric and elastic properties of Rochelle salt has been performed for the first time.

“…Analogous results were obtained in [48,50] in their studies of the transverse electric field dependence of the transverse dielectric susceptibility of glycinium phosphite.…”

supporting

confidence: 75%

The effect of transverse electric fields on dielectric, piezoelectric, elastic and thermal properties of the Rochelle salt NaKC_{4}H_{4}O_{6} · 4H_{2}O

Levitskii¹,

Zachek²,

et al. 2009

“…It is shown that the dependences T c (E 1,3 ) are close to quadratic in the fields (see [10]), and at the fields up to 4 MV/m, they can be written as: With an increase of strength of the electric field E 1 , the spontaneous polarization P 2 slightly decreases, but polarization P 1 induced by the field increases. Polarization P 3 induced by the field E 1 is negative, and in magnitude it is three times larger than the P 1 .…”

Section: Comparison With the Experimental Datamentioning

confidence: 94%

“…The results of an experimental investigation of the static dielectric permittivity ε 33 of GPI crystal at different values of the field E 3 are presented in [10,11]. The phase transition temperature for this case was 222 K, but the field dependence of the T c is similar to the crystal with T c = 225 K. Therefore, having made the above mentioned changes of the model parameters, we consider it possible to explain the experimental data.…”

Section: Comparison With the Experimental Datamentioning

confidence: 95%

Influence of electric fields on dielectric properties of GPI ferroelectric

Zachek¹,

Левицкий²,

et al. 2017

Using modified microscopic model of GPI by taking into account the piezoelectric coupling with strains ε i in the frames of two-particle cluster approximation, the components of polarization vector and static dielectric permittivity tensor of the crystal at applying the external transverse electric fields E 1 and E 3 are calculated. An analysis of the influence of these fields on thermodynamic characteristics of GPI is carried out. A satisfactory quantitative description of the available experimental data for these characteristics has been obtained at a proper choice of the model parameters.

“…The experiment, carried out in [34], revealed anomalies of permittivity ε zz in the phase transition region at E z 0 and a decrease of the phase transition temperature proportional to E 2 z . For the first time, the explanation of the revealed effects was given on the basis of phenomenologic theory [35] and within microscopic approach [34,36]. Unfortunately, a complete quantitative description of these experimental data was not obtained.…”

Section: Introductionmentioning

confidence: 99%

Deformation effects in glycinium phosphite ferroelectric

Zachek¹,

Левицкий²,

2018

To study the effects appearing under mechanical stresses, we have used the model of glycinium phosphite ferroelectric, modified by taking into account the piezoelectric coupling of ordering structure elements with lattice strains. In the frames of two-particle cluster approximation, the components of polarization vector and static dielectric permittivity tensor of the crystal, as well as its piezoelectric and thermal characteristics are calculated. Influence of shear stresses, hydrostatic and uniaxial pressures on the phase transition and physical characteristics of the crystal is studied.