Related papers: Electrocaloric effect in KH$_2$PO$_4$
The proton ordering model for the KH$_{2}$PO$_{4}$ type ferroelectrics is modified by taking into account the dependence of the effective dipole moments on the proton ordering parameter. Within the four-particle cluster approximation we…
Using the proton ordering model modified by taking into account the dependence of the dipole moments on the order parameter [Vdovych et al, 2014], we explore the piezocaloric and multicaloric effects in the KH$_{2}$PO$_{4}$ type…
To investigate the caloric effects in the CsH$_2$PO$_4$ ferroelectric, a modified pseudospin model of this crystal is used, which takes into account the dependence of the parameters of interaction between pseudospins on lattice strains. The…
The origin of ferroelectricity in KH_2PO_4 (KDP) is studied by first-principles electronic structure calculations. In the low-temperature phase, the collective off-center ordering of the protons is accompanied by an electronic charge…
We present the results of the thermodynamic theory of piezoelectric ferroelectrics and of the phenomenological theory of thermodynamic characteristics of the KH$_{2}$PO$_{4}$ type ferroelectrics. Available experimental data for the…
Within the modified model of proton ordering of one-dimensional ferroelectric having hydrogen bonds of PbHPO$_4$-type, their thermodynamic and dynamic characteristics are studied and calculated taking into account the linear (by crystal…
Within the four-particle cluster approximation for the proton ordering model we study the influence of shear stress $\sigma_6$ on the phase transition, static dielectric, elastic and thermal properties of deuterated KD2PO4 type…
We propose a two-sublattice proton ordering model for the quasione-dimensional CsH$_2$PO$_4$ ferroelectric with hydrogen bonds, which takes into account linear on lattice strains $u_1$, $u_2$, $u_3$ and $u_5$ contribution to the energy of…
Within the framework of a modified proton ordering model of the KH_{2}PO_{4} family ferroelectric crystals, taking into account a linear over the strain \varepsilon_{6} contribution into the proton system energy, we obtain an expression for…
We verify whether the previously developed model of a KD2PO4 crystal, with the shear strain eps6 taken into account, is able to describe the longitudinal electric field E3 influence on the KH2PO4 family ferroelectrics. Major effects of the…
An atomistic effective Hamiltonian is used to compute electrocaloric (EC) effects in rare-earth substituted BiFeO$_{3}$ multiferroics. A phenomenological model is then developed to interpret these computations, with this model indicating…
A new approach in the investigation of the order parameter behaviour near ferroelectric phase transition point is suggested. The short range and dipole interactions between particles are taken into account. The logarithmic corrections and…
The model of NH$_3$CH$_2$COOH$\cdot$H$_2$PO$_3$, modified by taking into account the piezoelectric coupling between the ordering structure elements and the strains $\varepsilon_i$, $\varepsilon_j$, is used for investigation of the effects…
Using modified microscopic model of GPI by taking into account the piezoelectric coupling with strains $\varepsilon_i$ in the frames of two-particle cluster approximation, the components of polarization vector and static dielectric…
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…
Ferroelectric ordering, the electroclinic effect and chiral smectic C (SmC*) - smectic A (SmA*) phase transitions in thin planar ferroelectric liquid crystal (FLC) cells are studied by means of linear electrooptic and second harmonic…
Using the previously developed model we revisit the problem of the electric field induced polarization rotation in antiferroelectric crystals of squaric acid. We test an alternative set of the model parameters, according to which the dipole…
While all of the polymorphs of pure NH$_4$I and KI are non-polar, we identify that (NH$_4$)$_{0.95}$K$_{0.05}$I is ferroelectric and (NH$_4$)$_{0.87}$K$_{0.13}$I and (NH$_4$)$_{0.83}$K$_{0.17}$I are pyroelectric through measurements of…
The transmission electron microscopy observations of the charge ordering (CO) which governs the electronic polarization in LuFe2O4-x clearly show the presence of a remarkable phase separation at low temperatures. Two CO ground states are…
We analyze a system of polar molecules in a one-dimensional optical lattice. By controlling the internal structure of the polar molecules with static electric and microwave fields, we demonstrate the appearance of a quantum phase transition…