相关论文: Epitaxially strained SnTiO$_{3}$ at finite tempera…
First-principles total-energy calculations are carried out for (001) surfaces of the cubic perovskite ATiO3 compounds PbTiO3, BaTiO3, and SrTiO3. Both AO-terminated and TiO2-terminated surfaces are considered, and fully-relaxed atomic…
The structural transformation of multiferroic EuTiO$_3$ has been intensively investigated by synchrotron x-ray diffraction at pressures up to 50.3 GPa and temperatures from 50 to 500 K. An antiferrodistortive phase transition from cubic…
Many dipolar topological structures have been experimentally demonstrated in (PbTiO$_3$)$_n$/(SrTiO$_3$)$_n$ superlattices, such as flux-closure, vortice, and skyrmion. In this work, we employ deep potential molecular dynamics (MD) to…
The behavior of PbTiO$_3$ under uniaxial strains and stresses is investigated from first-principles calculations within density functional theory. We show that irrespectively of the uniaxial mechanical constraint applied, the system keeps a…
We study the complex ferroelastic/ferroelectric domain structure in the prototypical ferroelectric PbTiO3 epitaxially strained on (110)o-oriented DyScO3 substrates, using a combination of atomic force microscopy, laboratory and synchrotron…
We performed first principles calculations for epitaxially strained orthorhombic CaTiO$_3$. The computational results reveal the existence of a metastable ferroelectric phase at compressive strain with unexpected in-plane polarization.…
We identify a first-order, isosymmetric transition between a ferrielectric (FiE) and ferroelectric (FE) state in $A$-site ordered LaScO$_{3}$/BiScO$_{3}$ and LaInO$_{3}$/BiInO$_{3}$ superlattices. Such a previously unreported ferroic…
Epitaxial strain provides important pathways to control the magnetic and electronic states in transition metal oxides. However, the large strain is usually accompanied by a strong reduction of the oxygen vacancy formation energy, which…
Transition metal oxides are considered promising thermoelectric materials for harvesting high-temperature waste heat due to their stability, abundance and low toxicity. Despite their typically strong ionic character, they can exhibit…
By a combination of first-principles calculations and semi-classical Boltzmann transport theory, we investigate the effect of epitaxial strain on the electronic structure and transport properties of PtCoO$_2$ and PdCoO$_2$. In contrast to…
Piezoelectrics interconvert mechanical energy and electric charge and are widely used in actuators and sensors. The best performing materials are ferroelectrics at a morphotropic phase boundary (MPB), where several phases can intimately…
We demonstrate how the quantum paraelectric ground state of SrTiO$_3$ can be accessed via a microscopic $ab~initio$ approach based on density functional theory. At low temperature the quantum fluctuations are strong enough to stabilize the…
SrTiO$_3$ is an incipient ferroelectric on the verge of a polar instability, which is avoided at low temperatures by quantum fluctuations. Within this unusual quantum paraelectric phase, superconductivity persists despite extremely dilute…
We use \textit{ab initio} calculations to systematically study the phase diagram of multiferroic Sr$_{1-x}$Ba$_x$MnO$_3$ ($0 \leq x \leq 1$) as a function of chemical doping, epitaxial strain and external pressure. We find that by replacing…
Since its original prediction 25 years ago, room-temperature out-of-plane ferroelectricity in compressively strained SrTiO3 remains an ongoing pursuit. In this work, we investigate the structural, electrical and electromechanical properties…
Density functional theory is used to investigate the effect of biaxial strain on the structural, electronic and magnetic properties of [111]-oriented NdNiO$_3$, as a representative of the rare-earth perovskites that undergo…
Despite important breakthroughs in the last decade, the calculation of temperature dependent properties of solids still remains a challenging task, especially in the vicinity of structural phase transitions. We show that the combination of…
A method for the calculation of the temperature dependence of dielectric and piezoelectric responses, based on the use of a first-principles effective Hamiltonian, is described. Results are presented for the ferroelectric perovskite PbTiO3.…
Epitaxial strain can be used to modify the properties of ferroelectric thin films. From the experimental viewpoint, the challenge is to fine-tune the magnitude of the strain. We illustrate how, by using a suitable combination of composition…
We have fabricated PbTiO$_{3}$/SrRuO$_{3}$ superlattices with ultra-thin SrRuO$_{3}$ layers. Due to the superlattice geometry, the samples show a large anisotropy in their electrical resistivity, which can be controlled by changing the…