相关论文: Electrocaloric effect in KH$_2$PO$_4$
Neutron diffraction measurements on multiferroic LuFe2O4 show changes in the antiferromagnetic (AFM) structure characterized by wavevector q = (1/3 1/3 1/2) as a function of electric field cooling procedures. The increase of intensity from…
In heavy atoms and ions, nuclear structure effects are significantly enhanced due to the overlap of the electron wave functions with the nucleus. This overlap rapidly increases with the nuclear charge $Z$. We study the energy level shifts…
Interfacial ferroelectricity, prevalent in various parallel-stacked layered materials, allows switching of out-of-plane ferroelectric order by in-plane sliding of adjacent layers. Its resilience against doping potentially enables…
We present a minimal Landau theory of plastic-to-crystal phase transitions in which the key components are a multipole-moment order parameter that describes the orientational ordering of the constituent molecules, coupling between such…
We present a simple theory for structural transitions in displacive ferroelectrics of the perovskite type. In our theory, the competition between the elastic energy cost for the displacement of the homopolar ion from the centrosymmetric…
We study analytically the finite-temperature phase diagram of proton ordering of a quasi-two dimensional hydrogen-bonded system, namely the squaric acid crystal($\text{H}_2\text{C}_4\text{O}_4$). We take into account the four-spin…
Temperature measurements of dielectric permittivity are performed for nonstoichiometric ferroelectric lead germanate Pb$_{4.95}$Ge$_3$O$_{11}$ and multiferroic solid solution [N(C$_2$H$_5$)$_4$]$_2$CoClBr$_3$. Unlike the heat capacity data,…
Measurements of ferroelectric polarization and dielectric constant were done on $R$Mn$_2$O$_5$ ($R$=Tb, Dy, and Ho) with applied hydrostatic pressures of up to 18 kbar. At ambient pressure, distinctive anomalies were observed in the…
We report the properties of two new series of compounds that show the ferroelectric nematic phase in which the length of a terminal chain is varied. The longer the terminal chain, the weaker the dipole-dipole interactions of the molecules…
Ferroelectric materials are characterized by a spontaneous polar distortion. The behavior of such distortions in the presence of free charge is the key to the physics of metallized ferroelectrics in particular, and of structurally-polar…
The four-state model is proposed for description of phase transition in ferroelectric crystals of DMAGaS and DMAAlS type. Thermodynamical functions of the model are obtained in the mean field approximation. The phase transition between…
An eight-potential-well order-disorder ferroelectric model was presented and the phase transition was studied under the mean-field approximation. It was shown that the two-body interactions are able to account for the first-order and the…
We present a study of the dielectric, structural, and magnetic properties of the multiferroic or linear magnetoelectric substitution series [(NH$_4$)$_{1-x}$K$_x$]$_2$[FeCl$_5$(H$_2$O)]. Pyroelectric currents, magnetic susceptibilities, and…
We suggest a random field based model for calculation of physical properties of mixed ferroelectric relaxors. Our model naturally incorporates the different orientations of electric dipoles (related to different solid solution components)…
Magnetoelectric properties of a coupled spin-electron model on a doubly decorated square lattice in an external electric field applied along the crystallographic axis [11] are rigorously examined with the help of generalized…
We study the extended Hubbard model away from half-filling on a two-dimensional square lattice using cluster dynamical mean field theory on clusters of size $8$. We show that the model exhibits metallic, compressible charge ordered, and…
Comprehensive review of investigations of substances with a small difference in the energies of the ferroelectric and antiferroelectric types of dipole ordering is presented. Detailed analysis of the stability of homogeneous phases and…
Spontaneous polarization is essential for ferroelectric functionality in non-centrosymmetric crystals. High-integration-density ferroelectric devices require the stabilization of ferroelectric polarization in small volumes. Here,…
Using the previously developed model we explore the processes of polarization rotation in antiferroelectric crystals of squaric acid by the electric fields directed arbitrarily within the $ac$ plane. Except for some particular directions of…
In this letter, we report the structural, electronic and ferroelectric properties of the layered mixed-valent transition-metal compound, Sr$_{4}$Fe$_{6}$O$_{12}$ (SFO). We demonstrate how SFO undergoes a phase transition from a…