相关论文: Phonon in SrTiO$_3$ under finite electric fields
Time-resolved two color pump-probe polarization spectroscopy was performed at room temperature on SrTiO3 films grown directly on Si with film thickness varying from 2 nm to 7.8 nm. The E soft mode with a characteristic frequency of 0.2 THz…
Phonons are universal language for solid state theory. Effective phonon theory (self-consistent harmonic approximation) have been extensively used to access the weakly nonlinear effect in solid materials, which are standard content in…
The phonon spectrum of cubic cadmium metastannate and the crystal structures of its distorted phases were calculated from first principles within the density functional theory. It is shown that the phonon spectrum and the energy spectrum of…
We use first principles density functional theory to investigate the softening of polar phonon modes in rutile TiO$_2$ under tensile (110)-oriented strain. We show that the system becomes unstable against a ferroelectric distortion with…
The structure, magnetic properties, and lattice dynamics of ordered Fe-Pt alloys with three stoichiometric compositions, Fe$_3$Pt, FePt and FePt$_3$, have been investigated using the density functional theory. Additionally, the existing…
We study a massive real scalar field that breaks translation symmetry dynamically. Higher-gradient terms favour modulated configurations and neither finite density nor temperature are needed. In the broken phase, the energy density depends…
A new variational approach is proposed at zero temperature for a finite density of charge carriers in order to study ground state features of the Frohlich model including electron-electron and electron-phonon interactions. Within the…
Phononic properties are commonly studied by calculating force constants using the density functional theory (DFT) simulations. Although DFT simulations offer accurate estimations of phonon dispersion relations or thermal properties, but for…
In bilayer CrI3, experimental and theoretical studies suggest that the magnetic order is closely related to the layer staking configuration. In this work, we study the effect of dynamical lattice distortions, induced by non-linear phonon…
Phonon hydrodynamics is an exotic phonon transport phenomenon that challenges the conventional understanding of diffusive phonon scattering in crystalline solids. It features a peculiar collective motion of phonons with various…
We calculate the phonon-dispersion relations of several two-dimensional materials and diamond using the density-functional based tight-binding approach (DFTB). Our goal is to verify if this numerically efficient method provides sufficiently…
Recent experiments demonstrate precise control over coherently excited circular phonon modes using high-intensity terahertz lasers, opening new pathways towards dynamical, ultrafast design of magnetism in functional materials. While the…
The transport and magnetic properties of correlated La{0.53}Sr{0.47}MnO{3} ultrathin films, grown epitaxially on SrTiO{3}, show a sharp cusp at the structural transition temperature of the substrate. Using a combination of experiment and…
We study how phonon structure manifests itself in the electronic density of states of graphene. A procedure for extracting the value of the electron-phonon renormalization $\lambda$ is developed. In addition, we identify direct phonon…
We present a review of the basic ideas and techniques of the spectral density functional theory which are currently used in electronic structure calculations of strongly-correlated materials where the one-electron description breaks down.…
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…
We calculate the lattice dielectric function of strongly anharmonic rutile $\mathrm{TiO}_2$ from ab initio anharmonic lattice dynamics methods. Since an accurate calculation of the $\Gamma$ point phonons is essential for determining optical…
A introduction into density-functional theory and electronic structure methods is given, that aims at providing an intuitive understanding of the underlying concepts for the novice as well as an entry point towards the more advanced…
We discuss the electronic structure, lattice dynamics and electron-phonon interaction of newly discovered superconductor LaO$_{0.5}$F$_{0.5}$BiS$_{2}$ using density functional based calculations. A strong Fermi surface nesting at…
The self consistent version of the density functional theory (DFT) is presented, which allows to calculate the ground state and dynamic properties of finite multi-electron systems such as atoms, molecules and clusters. The exact functional…