Related papers: Dipolar Nematic State in Relaxor Ferroelectrics
Only a few years have passed since discovery of polar nematics, and now they are becoming the most actively studied liquid crystal materials. Despite numerous breakthrough findings made recently, a theoretical systematization is still…
We develop a lattice model for the splay flexoelectric effect in nematic liquid crystals. In this model, each lattice site has a spin representing the local molecular orientation, and the interaction between neighboring spins represents…
The realization of a spontaneous macroscopic ferroelectric order in fluids of anisotropic mesogens is a topic of both fundamental and technological interest. Recently, we demonstrated that a system of dipolar achiral disklike ellipsoids can…
We analyzed the domain morphology, electrocaloric response, and negative capacitance states in a one-dimensional array of uniformly oriented, radial symmetric ferroelectric nanowires, whose spontaneous polarization is normal to their…
The role of defects in solids of mixed ionic-covalent bonds such as ferroelectric oxides is complex. Current understanding of defects on ferroelectric properties at the single-defect level remains mostly at the empirical level, and the…
Monte Carlo simulations are used to examine cooperative creation of polar state in fluids of two-state particles with nonzero dipole in the excited state. With lowering temperature such systems undergo a second order transition from…
The model discussion focused on links between the unique properties of relaxor ceramics and the basics of critical phenomena physics and glass transition physics. It indicates the significance of uniaxiality for appearing mean-field…
We have measured the bending-induced polarization of Pb(Mg1/3Nb2/3)O3-PbTiO3 single crystals with compositions at the relaxor-ferroelectric phase boundary. The crystals display very large flexoelectricity, with flexocoupling coefficients an…
We propose a simple and solvable mean-field model of the scattering of transverse optic modes by Polarized Nano Regions (PNR) in the paraelectric phase of relaxor ferroelectrics. The PNR is assumed to be a ferroelectric sphere embedded in…
A Landau-type phenomenological cluster theory was presented to model the freezing process of local polarization in relaxors. Based on the theory, the proportion of frozen polarization in Pb(Mg$_{1/3}$Nb$_{2/3}$)O$_3$-PbTiO$_3$ (PMNT) was…
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…
The electrocaloric effect (ECE) in normal and relaxor ferroelectrics is investigated in the framework of a thermodynamic approach based on the Maxwell relation and a Landau-type free energy model. The static dielectric response of relaxors…
Recent discovery of the ferroelectric nematic phase N_F resurrects a question about stability of the uniform N_F state with respect to the formation of either standard for solid ferroelectrics domain structure, or often occurring in liquid…
Ferroelectric materials are characterized by the presence of an electric dipole that can be reversed by application of an external electric field, a feature that is exploited in ferroelectric memories. All ferroelectrics are piezoelectric,…
A simple model to reproduce strong enhancement of dielectric response near the morphotropic phase boundary (MPB) is proposed. This model consists of long-range dipole-dipole interaction and compositional chemical disorder incorporated by…
The colloidal processing of nearly monodisperse and highly crystalline single-domain ferroelectric or ferromagnetic nanocubes is a promising route to produce superlattice structures for integration into next-generation devices, whereas…
The recently discovered ferroelectric nematic liquid crystals have been reported to exhibit very large dielectric permittivity values. Here, we report a systematic investigation of the dielectric behavior of a prototypical ferroelectric…
Ferroelectric domain structure evolution induced by an external electric field was investigated by means of nematic liquid crystal (NLC) method in two strontium-barium niobate single crystals of nominal composition:…
Results of detailed investigations of stability of phases in substances with the small difference in the energies of the ferroelectric and the antiferroelectric types of dipole ordering are presented. It is shown that interaction of locally…
In this paper, we present a microscopic model for heterogeneous ferroelectric and an order parameter for relaxor phase. We write a Landau theory based on this model and its application to ferroelectric PbFe$_{1/2}$Ta$_{1/2}$O$_3$ (PFT) and…