Related papers: Diffusive phase transitions in ferroelectrics and …
Size-driven transition of an antiferroelectric into a polar ferroelectric or ferrielectric state is a strongly debated issue from both experimental and theoretical perspectives. While critical thickness limits for such transitions have been…
We have proposed the phenomenological description of dielectric hysteresis loops in ferroelectric semiconductors with charged defects and prevailing extrinsic conductivity. Exactly we have modified Landau-Ginsburg approach and shown that…
We show that nano-scale variations of the order parameter in strongly-correlated systems can induce local spatial regions such as domain walls that exhibit electronic properties representative of a different, but nearby, part of the phase…
We develop a minimal Landau theory for the concomitant intersite charge-transfer, antiferromagnetic, and isostructural phase transitions in ACu$_3$Fe$_4$O$_{12}$ perovskites (A = La, Pr, Nd, Sm, Eu, Gd, Tb). The model incorporates the…
At room temperature, GdMnO3 is a paraelectric and paramagnetic with a distorted perovskite structure of orthorhombic symmetry (space group Pnma). On cooling, it undergoes a phase transition sequence to a magnetic incommensurate phase…
In this work we use a phenomenological theory of ferroelectric switching in BiFeO$_3$ thin films to uncover the mechanism of the two-step process that leads to the reversal of the weak magnetization of these materials. First, we introduce a…
Ferroelectric hafnium zirconium oxide (HZO) thin films show significant promise for applications in ferroelectric random-access memory, ferroelectric field-effect transistors, and ferroelectric tunneling junctions. However, there are…
Neutron scattering measurements of the lowest-energy TO phonons in the relaxor Pb(Mg1/3Nb2/3)O3 (PMN) are reported for 10<=T<=750 K. The soft mode, which is overdamped by the polar nanoregions below the Burns temperature T_d = 620 K,…
Recently, a layered ferroelectric CuInP2Se6 was shown to exhibit domain walls with locally enhanced piezoresponse - a striking departure from the observations of nominally zero piezoresponse in most ferroelectrics. Although it was proposed…
Ground state properties and phonon dispersion curves of a classical linear chain model describing a crystal with an incommensurate phase are studied. This model is the DIFFOUR (discrete frustrated phi4) model with an extra fourth-order term…
We study the electrical behavior of multiferroic BiFeO$_3$ by means of first-principles calculations. We do so by constraining a specific component of the electric displacement field along a variety of structural paths, and by monitoring…
Phase field crystal (PFC) models constitute a field theoretical approach to solidification, melting and related phenomena at atomic length and diffusive time scales. One of the advantages of these models is that they naturally contain…
We study the dynamics of vortex lines in Supercondutor/Ferromagnet/Superconductor (SFS) heterostructures at microwave frequencies. We have employed swept-frequency, Corbino-disk and resonant, dielectric-resonator techniques to obtain the…
The structural and polar properties of BiFeO3 at finite temperature are investigated using an atomistic shell model fitted to first-principles calculations. Molecular Dynamics simulations show a direct transition from the low-temperature…
A stochastic model for the field-driven polarization reversal in rhombohedral ferroelectrics is developed, providing a description of their temporal electromechanical response. Application of the model to simultaneous measurements of…
Dielectric nonlinear response of (PbMg$_{1/3}$Nb$_{2/3}$O$_3$)$_{0.9}$(PbTiO$_3$)$_{0.1}$ (0.9PMN-0.1PT) relaxor ceramics was investigated under different ac drive voltages. It was observed that: (i) the dielectric permittivity is…
In this paper we study the size effects of the ferroelectric nanotube and nanowire phase diagrams and polar properties allowing for radial stress and depolarization field influence. The approximate analytical expression for the…
For relaxor-ferroelectrics and relaxor-ferromagnets, Ehrenfest classification of phase transitions based on the discontinuity of entropy or specific heat etc. with temperature (T) gives no transition that contradicts the measured order…
We study theoretically the influence of the underlying domain microstructure on the electromechanical properties of ferroelectrics. Our calculations are based on a continuum approach that incorporates the long-range elastic and…
Autferroics, recently proposed as a sister branch of multiferroics, exhibit strong intrinsic magnetoelectricity, but ferroelectricity and magnetism are mutually exclusive rather than coexisting. Here, a general model is considered based on…