相关论文: Ab initio based study on atomic ordering in {(Ba, …
We have constructed the surface phase diagram of the BaTiO$_{3}$(001) surface by employing an evolutionary algorithm for surface structure prediction, where the ferroelectric polarization is included as a degree of freedom. Among over 1000…
Full pattern Le-Bail refinement using x-ray powder diffraction profiles of Sr1-xCaxTiO3 for x=0.02, 0.04 in the temperature range 12 to 300 K reveals anomalies in the unit cell parameters at 170, 225 K due to an antiferrodistortive (cubic…
This letter addresses basic questions concerning ferroelectric order in positionally disordered dipolar materials. Three models distinguished by dipole vectors which have one, two or three components are studied by computer simulation.…
Ferroelectric ceramics (Ba0.85Ca0.15)(Ti0.9Zr0.1-xSnx)O3 (x=0.00, 0.02, 0.04, 0.06) were prepared by a sol-gel method. Structural investigation revealed the co-existence of tetragonal (P4mm) and orthorhombic (Pmm2) symmetries at room…
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 dielectric tuning and loss of (Ba,Sr)TiO3:MgO bulk composites depend strongly on the connectivity and interaction among the two phases. To investigate this relationship, the polar structure and dynamics of these composites is mapped as…
SrTiO3 is a textbook quantum paraelectric, with ferroelectricity purportedly suppressed by quantum fluctuations of ionic positions down to the lowest temperatures. The precise real space structure of SrTiO3 at low temperature, however, has…
Based on the earlier published theory (\textit{Nature Mat}. \textbf{18}, 223--228 (2019)), a comprehensive experimental investigation of multiferroic quantum critical behavior of (Eu,Ba,Sr)TiO$_3$ polycrystalline and single crystal samples…
Ferroelectric materials embedded with dielectric inclusions offer a unique platform for exploring novel topological polar textures. Using first-principles-based atomistic simulations, we investigate the polarization behavior of a BaTiO$_3$…
Accurately predicting the Curie temperature ($T_c$) of ferroelectrics from first principles remains a major challenge, as theoretical estimates often fall significantly below experimental values. In this work, we investigate the origin of…
We investigate the crystal structure in multiferroic tetragonal perovskite Sr$_{1/2}$Ba$_{1/2}$MnO$_3$ with high accuracy of the order of 10$^{-3}$ Angstrom for an atomic displacement. The large atomic displacement for Mn ion from the…
The effect of rare-earth ions (R = Er$_3^+$, Tb$_3^+$, and Ce$_{3.75}^+$) on the dielectric properties and the electric polarization induced by local polar phase separation domains in solid solutions of R$_{0.8}$Ce$_{0.2}$Mn$_2$O$_5$ (R =…
Pb-based perovskites with multiple cations are fascinating materials showing various phenomena such as high piezoelectric, electromechanical, and relaxor properties. While chemical disordering accompanied by polar nanoregions and nanosized…
Strongly correlated system with competing ground states are often poised close to the quantum critical point. External perturbations such as pressure, strain, electric field, and chemical doping can stabilise its ground state with exotic…
In order to gain insight into suppression of the ferromagnetic ordering temperature, local studies utilizing 99,101Ru zero-field spin-echo NMR, along with complimentary magnetization, high-angle x-ray diffraction, and Ru K-edge XAFS…
We investigate the electronic structure and the ferroelectric properties of the recently discovered multiferroic ScFeO$_3$ by means of ab-initio calculations. The $3d$ manifold of Fe in the half-filled configuration naturally favors an…
The ternary-arsenide compound BaCo2As2 was previously proposed to be in proximity to a quantum-critical point where long-range ferromagnetic (FM) order is suppressed by quantum fluctuations. Here we report the effect of Ir substitution for…
Specific heat studies of the Sr$_{1-x}$Ba$_x$Mn$_{1-y}$Ti$_y$O$_3$ polycrystalline samples performed by the relaxation and DSC methods over the temperature range 2 - 450 K are reported. Anomalies accompanying the…
Perovskite oxides attract increasing attention due to their broad potential in many applications. Understanding their surfaces is challenging, though, because the ternary composition of the bulk allows for multiple stable surface…
We carry out a completely first-principles study of the ferroelectric phase transitions in BaTiO$_3$. Our approach takes advantage of two features of these transitions: the structural changes are small, and only low-energy distortions are…