Related papers: Lattice dynamics and electronic transitions in a s…
We combine polarization-resolved low frequency Raman microscopy and dispersion-corrected density-functional calculations (DFT-D3) to study polymorph-dependent lattice vibrations in coronene, a model molecular system for nanographenes and…
Two recent preprints in the physics archive (arXiv) have called attention as they claim experimental evidence that a Cu-substituted apatite material (dubbed LK-99) exhibits superconductivity at room temperature and pressure. If this proves…
LaRh$_3$B$_2$ crystallizes in a layered structure where Rh atoms form a perfect Kagome lattice. The material shows superconductivity at $T_c \approx 2.6$~K\@ and no signature for density wave instabilities. We report our measurements of…
We investigate the electronic and magnetic properties as well as lattice dynamics and spin-phonon coupling of $\beta$-Na$_{0.33}$V$_2$O$_5$ using temperature-dependent Raman scattering, dc-magnetization and dc-resistivity, x-ray…
Employing a first-principles and model Hamiltonian approach, we work out the electronic properties of polar-polar LaVO$_3$/KTaO$_3$ (LVO/KTO, 001) heterostrctures, with up to six layers of KTO and five layers of LVO. Our analyses indicate…
Structural phase transition can occur due to complex mechanisms other than simple dynamical instability, especially when the parent and daughter structure is of low dimension. This article reports such an inversion symmetry-breaking…
Periodic band structures are a hallmark phenomenon of condensed matter physics. While often imposed by external potentials, periodicity can also arise through the interplay of couplings that are not necessarily spatially periodic on their…
The 3d electronic structure and phase transition in pure and Cr doped V2O3 are theoretically investigated in relation to the 3d spin-orbit interaction and lattice distortion. A model consisting of the nearest-neighbor V ion pair with full…
Phonon measurements in the A15-type superconductors were complicated in the past because of the unavailability of large single crystals for inelastic neutron scattering, e.g., in the case of Nb$_3$Sn, or unfavorable neutron scattering…
The hybrid halide perovskite CH3NH3PbI3 exhibits a complex structural behaviour, with successive transitions between orthorhombic, tetragonal and cubic polymorphs at ca. 165 K and 327 K. Herein we report first-principles lattice dynamics…
While 3$d$-containing materials display strong electron correlations, narrow band widths, and robust magnetism, 5$d$ systems are recognized for strong spin-orbit coupling, increased hybridization, and more diffuse orbitals. Combining these…
We report a polarized Raman scattering study of the lattice dynamics of $\beta$-Li$_2$IrO$_3$ under hydrostatic pressures up to 7.62 GPa. At ambient pressure, $\beta$-Li$_2$IrO$_3$ exhibits the hyperhoneycomb crystal structure and a…
In solids, the response of the lattice to photo-excitation is often described by the inertial evolution on an impulsively modified potential energy surface which leads to coherent motion. However, it remains unknown if vibrational coherence…
Electron-phonon interaction in copper oxide superconductors is still enigmatic. Strong coupling for certain optic phonons is now well established experimentally, but theoretical understanding is challenging. Scattering of electrons near the…
In quantum magnetic materials it is common to observe both static and dynamic lattice effects on the magnetic excitation spectrum. Less common is to find that the magnetic correlations have a significant impact on the phonon spectrum. Can…
We have performed extensive ab initio calculations to investigate phonon dynamics and their possible role in superconductivity in BaFe2As2 and related systems. The calculations are compared to inelastic neutron scattering data that offer…
In Eu2ZnIrO6, effectively two atoms are active i.e. Ir is magnetically active, which results in complex magnetic ordering within the Ir sublattice at low temperature. On the other hand, although Eu is a van-vleck paramagnet, it is active in…
The role of the crystal lattice for the electronic properties of cuprates and other high-temperature superconductors remains controversial despite decades of theoretical and experimental efforts. While the paradigm of strong electronic…
We investigated the electronic structure and lattice dynamics of multiferroic MnWO4 by optical spectroscopy. With variation of polarization, temperature, and magnetic field, we obtained optical responses over a wide range of photon…
Lattice effects on photo-excited states in interacting charge frustrated system are examined. Real time dynamics in the interacting spinless fermion model on a triangular lattice coupled to lattice vibration are analyzed by applying the…