Related papers: Ferroelectricity in strained Ca$_{0.5}$Sr$_{0.5}$T…
Nanometer-scale modulations can spontaneously emerge in complex materials when multiple degrees of freedom interact. Here we demonstrate that ferroelectric Sr$_{1-x}$Ca$_x$TiO$_3$ lies in close proximity to an incipient structurally…
The spin-induced ferroelectricity in quasi-1D spin chain system is little known, which could be fundamentally different from those in three-dimensional (3D) system. Here, we report the ferroelectricity driven by a tilted screw spin order…
The effect of Sr doping in BaTiO3 (BTO) with nominal compositions Ba0.80Sr0.20TiO3 (BSTO) have been explored in its structural, lattice vibration, dielectric, ferroelectric and electrocaloric properties. The temperature dependent dielectric…
Tailoring at will polar textures in ferroelectrics is critical for the development of nanoscale electronics and functional oxide technologies. Freestanding ferroelectric membranes have enabled studies of strain-induced polarization…
Bulk LiOsO3 was experimentally identified as a "ferroelectric" metal where polar distortions coexist with metallicity [Shi et al., Nature Materials 12, 1024 (2013)]. It is generally believed that polar displacements in a "ferroelectric"…
Neutron pair distribution function analysis and first principles calculations have been employed to study short-range correlations in heavily disordered dielectric material Sr$_x$Ba$_{1-x}$Nb$_2$O$_6$ ($x=0.35, 0.5$ and 0.61). The…
Using density functional theory we investigate the lattice instability and electronic structure of recently discovered ferroelectric metal LiOsO$_3$. We show that the ferroelectric-like lattice instability is related to the Li-O distortion…
Ferroelectric and ferromagnetic orders rarely coexist, and magnetoelectric coupling is even more scarce. A possible avenue for combining these orders is by interface design, where orders formed at the constituent materials can overlap and…
We have investigated the out-of-plane lattice relaxation related to the ferroelectric transitions in epitaxial BaTiO$_3$ (BTO) films using synchrotron X-ray diffraction. Under either compressive strain or tensile strain, there is evidence…
We studied strain-induced polarization and resulting conductivity in the nonpolar/nonpolar CaZrO3/SrTiO3 (CZO/STO) heterostructure (HS) system by means of first-principles electronic structure calculations. By modeling four types of CZO/STO…
We study the interplay of structural and polar distortions in hexagonal YMnO3 and short-period PbTiO3/SrTiO3 superlattices by means of first-principles calculations at constrained electric displacement field D. We find that in YMnO3 the…
Structural and electronic properties of CaCu{3}Ti{4}O{12} have been calculated using density-functional theory within the local spin-density approximation. After an analysis of structural stability, zone-center optical phonon frequencies…
The question whether excess electrons in SrTiO3 form free or trapped carriers is a crucial aspect for the electronic properties of this important material. This fundamental ambiguity prevents a consistent interpretation of the puzzling…
Based on a first-principles based multiscale approach, we study the polarity (P) of ferroelastic twin walls in SrTiO$_3$. In addition to flexoelectricity, which was pointed out before, we identify two new mechanisms that crucially…
Density functional calculations are performed to study the effect of epitaxial strain on PbZrO3. We find a remarkably small energy difference between the epitaxially strained polar R3c and nonpolar Pbam structures over the full range of…
The topographic and electronic structure of cleaved SrTiO3(001) surfaces were studied, employing samples that either had or had not been coated with Ti on their outer surfaces prior to fracture. In both cases, SrO- and TiO2-terminated…
Flat elastic sheets tend to display wrinkles and folds. From pieces of clothing down to two-dimensional crystals, these corrugations appear in response to strain generated by sheet compression or stretching, thermal or mechanical mismatch…
In pursuit of rational control of orbital polarization, we present a combined experimental and theoretical study of single unit cell superlattices of the correlated metal LaNiO$_3$ and the band insulator LaAlO$_3$. Polarized x-ray…
Hybrid improper ferroelectricity, where an electrical polarization can be induced via a trilinear coupling to two non-polar structural distortions of different symmetry, has recently been experimentally demonstrated for the first time in…
The ferroelectricity of the spiral magnets LiCu2O2 and LiCuVO4 was examined by calculating the electric polarizations of their spin spiral states on the basis of density functional theory with spin-orbit coupling. Our work unambiguously…