Related papers: Surface phonons in two-layer thin films of GeSe

Density Functional Theory (DFT) calculations not only allow to predict the vibrational and optical properties of solids but also to understand and disentangle the mechanisms playing a key role in the generation of coherent optical phonons.…

One way to reduce the lattice thermal conductivity of solids is to induce additional phonon surface scattering through nanostructures. However, how phonons interact with boundaries, especially at the atomic level, is not well understood. In…

We report first principles calculations of the phonon dispersions of PbTe both for its observed structure and under compression. At the experimental lattice parameter we find a near instability of the optic branch at the zone center, in…

Topological insulators are a novel class of quantum materials characterized by protected gapless surface or edge states but insulating bulk states which is due to presence of spin-orbit interactions and time-reversal symmetry. Such an…

Since it is now possible to record vibrational spectra at nanometer scales in the electron microscope it is of interest to explore whether defects such as dislocations or grain boundaries will result in measurable changes of the spectra.…

We review calculations and measurements of the phonon-dispersion relation of graphite. First-principles calculations using density-functional theory are generally in good agreement with the experimental data since the long-range character…

In their work, Yan et al. [Phys. Rev. B 88, 121403 (2013)] employing density functional perturbation theory (DFPT) calculations, demonstrate that silicene and germanene show weaker Kohn anomalies in the $\Gamma$-$E_g$ and $K$-$A_1$ phonon…

Intercalation offers a promising way to alter the physical properties of two-dimensional (2D) layered materials. Here we investigate the electronic and vibrational properties of 2D layered MoSe$_2$ intercalated with atomic manganese at…

Density Functional Theory (DFT) calculations show that the reversible Sn/Ge(111) $\sqrt{3}\times\sqrt{3} \leftrightarrow 3\times3$ phase transition can be described in terms of a surface soft phonon. The isovalent Sn/Si(111) case does not…

ZrSiS, an intriguing candidate of topological nodal line semimetals, was discovered to have exotic surface floating two-dimensional (2D) electrons [Phys. Rev. X 7, 041073 (2017)], which are likely to interact with surface phonons. Here, we…

Extensive inelastic neutron scattering measurements of phonons on a single crystal of CaFe2As2 allowed us to establish a fairly complete picture of phonon dispersions in the main symmetry directions. The phonon spectra were also calculated…

In this work, we present a model of the surface states of nonsymmorphic semimetals. These are derived from surface mass terms that lift the high degeneracy imposed in the band structure by the nonsymmorphic bulk symmetries. Reflecting the…

The hyperbolic dispersion relation of phonon-polaritons (PhPol) provides high-momentum states, highly directional propagation, subdiffractional confinement, large optical density of states, and enhanced light-matter interactions. In this…

Investigating dispersion surface morphology of sonic metamaterials is crucial in providing information on related phenomena as inertial coupling, acoustic transparency, polarisation, and absorption. In the present study, we look into…

The IR- and Raman-active phonon frequencies, as well as the elastic constants of orthorhombic GeSe, were calculatedas a function of hydrostatic pressure using the method of density functional in the ABINIT software package. Comparison with…

Knowing the influence of the substrate type on the diffusion coefficient and the momentum relaxation in graphene is of great importance for the development of new device models specifically adapted to the peculiarities of this material. In…

Phonon polaritons (PhPs) are long-lived electromagnetic modes that originate from the coupling of infrared photons with the bound ionic lattice of a polar crystal. Cubic-Boron nitride (cBN) is such a polar, semiconductor material, which due…

Surface plasmons or phonons propagating on a two-dimensional (2D) material can exhibit coupling with resonant excitations in its substrate, and the resulting coupled modes were extensively studied. Similar coupling of edge modes propagating…

Using $\approx$40 fs ultrashort laser pulses, we investigate the picosecond acoustic response from a prototypical phase change material, thin Ge$_{2}$Sb$_{2}$Te$_{5}$ (GST) films with various thicknesses. After excitation with a 1.53…

Magnetic layered materials have emerged recently as promising systems to introduce magnetism in structures based on two-dimensional (2D) materials and to investigate exotic magnetic ground states in the 2D limit. In this work, we apply high…