相关论文: Elastocaloric response of PbTiO3 predicted from a …
We use molecular dynamics simulations for a first principles-based effective Hamiltonian to calculate two important quantities characterizing the electrocaloric effect in BaTiO$_3$, the adiabatic temperature change $\Delta T$ and the…
An effective Hamiltonian for the ferroelectric transition in $PbTiO_3$ is constructed from first-principles density-functional-theory total-energy and linear-response calculations through the use of a localized, symmetrized basis set of…
An effective Hamiltonian for the ferroelectric transition in PbTiO3 is constructed from first-principles density-functional-theory total-energy and linear-response calculations through the use of a localized, symmetrized basis set of…
The various approximations used in the construction of a first-principles effective Hamiltonian for BaTiO3, and their effects on the calculated transition temperatures, are discussed. An effective Hamiltonian for BaTiO3 is constructed not…
We study the impact of thermal hysteresis at the first-order structural/ferroelectric phase transitions on the electrocaloric response in bulk BaTiO$_3$ by performing molecular dynamics simulations for a first-principles-based effective…
The perovskite crystal BaTiO3 is modeled using a first-principles based effective Hamiltonian and molecular dynamics simulations are performed to estimate the pyroelectric response. The electrocaloric temperature change, \DeltaT, is…
Monte Carlo simulations with an effective Hamiltonian parametrized from first principles are performed to study the dielectric response of BaTiO3 as a function of temperature, with particular emphasis on the behavior of the dielectric…
Using an effective Hamiltonian parametrized from first principles, Monte Carlo simulations are performed in order to study the piezoelectric response of BaTiO3 in the ferroelectric tetragonal phase as a function of temperature. The effect…
We address the question of how the electrocaloric effect in epitaxial thin films of the prototypical ferroelectric BaTiO$_3$ is affected by the clamping to the substrate and by substrate-induced misfit strain. We use molecular dynamics…
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.…
The electrocaloric effect (ECE) in BaTiO3 is simulated using two different first-principles based effective Hamiltonian molecular dynamics methods. The calculations are performed for a wide range of temperatures (30--900 K) and external…
A newly developed fast molecular-dynamics method is applied to BaTiO3 ferroelectric thin-film capacitors with short-circuited electrodes or under applied voltage. The molecular-dynamics simulations based on a first-principles effective…
We study the electrocaloric (EC) effect in bulk BaTiO$_3$ (BTO) using molecular dynamics simulations of a first principles-based effective Hamiltonian, combined with direct measurements of the adiabatic EC temperature change in BTO single…
We investigate the effect of epitaxial strain on the electrocaloric effect (ECE) in BaTiO$_3$ by means of ab initio based molecular dynamics simulations. We show that tensile strain can be used to optimize the operation range for ferroic…
The phase-transition sequence of a ferroelectric perovskite such as BaTiO_3 can be simulated by computing the statistical mechanics of a first-principles derived effective Hamiltonian [Zhong, Vanderbilt and Rabe, Phys. Rev. Lett. 73, 1861…
We develop a first-principles scheme to study ferroelectric phase transitions for perovskite compounds. We obtain an effective Hamiltonian which is fully specified by first-principles ultra-soft pseudopotential calculations. This approach…
The first-principles-based effective Hamiltonian scheme provides one of the most accurate modeling technique for large-scale structures, especially for ferroelectrics. However, the parameterization of the effective Hamiltonian is…
The influence of defect dipoles on the electrocaloric effect (ECE) in acceptor doped BaTiO$_3$ is studied by means of lattice-based Monte-Carlo simulations. A Ginzburg-Landau type effective Hamiltonian is used. Oxygen vacancy-acceptor…
The mechanocaloric effect is the temperature change of a material upon application or removal of an external stress. Beyond its fundamental interest, this caloric response represents a promising and ecofriendly alternative to current…
We report modifications of the ferroelectric and electrocaloric properties of BaTiO$_3$ by defects. For this purpose, we have combined \textit{ab initio}-based molecular dynamics simulations with a simple model for defects. We find that…