Related papers: Electromechanical behavior of BaTiO3 from first pr…
We demonstrate room temperature ferroelectricity in the epitaxial thin films of magnetoelectric GaFeO3. Piezo-force measurements show a 180o phase shift of piezoresponse upon switching the electric field indicating nanoscale…
Artificial multiferroics consist of two types of ferroic materials, typically a ferroelectric and ferromagnet, often coupled interfacially by magnetostriction induced by the lattice elongations in the ferroelectric. In BaTiO3 the magnitude…
Based on detailed first-principles calculations, we investigate the tetragonal-to-hexagonal phase transition in Fe-doped BaTiO$_3$. Total energy calculations confirm a crossover from the tetragonal to hexagonal phases around 4\% Fe, in…
A mechanically coupled phase-field model is proposed for the first time to simulate the peculiar behavior of relaxor ferroelectrics. Based on the random field theory for relaxors, local random fields are introduced to characterize the…
Quantum Monte Carlo simulations offer an unbiased means to study the static and dynamic properties of quantum critical systems, while quantum field theory provides direct analytical results. We study three dimensional, critical quantum…
We construct an effective Hamiltonian via Monte Carlo from a given action. This Hamiltonian describes physics in the low energy regime. We test it by computing spectrum, wave functions and thermodynamical observables (average energy and…
We consider consequences of local disorder in systems experiencing first order phase transitions. Such systems can be of rather different nature. For example, manganates showing gigantic magnetoelectric effect, doped antiferroelectrics or…
BaTiO$_3$ (BTO) is a prototypical perovskite ferroelectric, whose dielectric permittivity and loss spectra -- which are strongly temperature and frequency dependent -- include contributions from inhomogeneous polarization patterns, with…
Measurements of the structure of hexagonal RMnO3 (R=rare earths (Ho) and Y) for temperatures significantly above the ferroelectric transition temperature (TFE) were conducted to determine the nature of the transition. The local and long…
The temperature-dependent polarization of SrTiO_3 thin films is investigated using confocal scanning optical microscopy. A homogeneous out-of-plane and inhomogeneous in-plane ferroelectric phase are identified from images of the linear…
The electronic structures of ABO3 ferroelectrics are calculated within the density functional theory, and their evolution is analyzed as the crystal-field symmetry changes from cubic to rhombohedral via tetragonal phases. Electronic…
We have studied the structural phase transition of multiferroic YMnO$_3$ from first principles. Using group-theoretical analysis and first-principles density functional calculations of the total energy and phonons, we perform a systematic…
We present Monte Carlo and Langevin micromagnetic calculations to investigate thermal switching of single-domain ferromagnetic particles. For the Monte Carlo study we place particular emphasis on the probability that the magnetization does…
EuTiO_{3} undergoes a structural phase transition from cubic to tetragonal at T_S = 282 K which is not accompanied by any long range magnetic order. However, it is related to the oxygen ocathedra rotation driven by a zone boundary acoustic…
Fe doping into BaTiO3, stabilizes the paraelectric hexagonal phase in place of the ferroelectric tetragonal one [P. Pal et al. Phys. Rev. B, 101, 064409 (2020)]. We show that simultaneous doping of Bi along with Fe into BaTiO3 effectively…
We have conducted a detailed high-pressure (HP) investigation on $Eu-$doped $BaTiO_3$ using angle-resolved x-ray diffraction, Raman spectroscopy, dielectric permittivity and dc resistance measurements. The x-ray diffraction data analysis…
Temperature dependent structural changes in a nearly pure monoclinic phase composition (x=0.525) of Pb(Zr_xTi_1-x)O_3 (PZT) have been investigated using Rietveld analysis of high-resolution synchrotron powder x-ray diffraction data and…
Structural phase transformations of [110] electric field cooled Pb(Mg1/3Nb2/3)O3-30%PbTiO3 (PMN-30%PT) crystals have been performed by x-ray diffraction in a field-cooled (FC) condition. A phase sequence of…
The magnetic moments of ${}^2{H}$, ${}^3{He}$ and ${}^3{H}$ as well as the thermal neutron capture rate on the proton are calculated using heavy baryon chiral perturbation theory {\it \`{a} la} Weinberg. The M1 operators have been derived…
Using a combination of first-principles and effective-Hamiltonian approaches, we map out the structure of BaTiO3 under epitaxial constraints applicable to growth on perovskite substrates. We obtain a phase diagram in temperature and misfit…