Related papers: Robust coherent phonon mode at GaP/Si(001) heteroi…
This study presents the first-principles phonon calculations to understand the experimental thermal expansion ($\alpha(T)$) and lattice thermal conductivity ($\kappa_{L}$) of CoSi at high temperature region. Phonon dispersion is computed…
We have determined the growth mode of graphene on SiC(0001) and SiC(000-1) using ultra-thin, isotopically-labeled Si13C `marker layers' grown epitaxially on the Si12C surfaces. Few-layer graphene overlayers were formed via thermal…
Coherent detection and interferometry in the terahertz (THz) regime are key capabilities that enable applications ranging from astronomy to non-destructive testing. Phase-sensitive THz detection is currently achieved using nonlinear…
We extend concepts from microwave engineering to thermal interfaces and explore the principles of impedance matching in 1D. The extension is based on the generalization of acoustic impedance to non linear dispersions using the contact…
We investigate the electronic background as well as the O2-O3 mode at 330 cm^-1 of highly doped YbBa2Cu3O7-delta in B1g symmetry. Above the critical temperature Tc the spectra consist of an almost constant electronic background and…
The optical reflectivity of Pb$_{0.865}$Sn$_{0.135}$Se and Pb$_{0.75}$Sn$_{0.25}$Se solid solutions was measured in the THz spectral region energetically corresponding to bulk optical phonon excitations and in the temperature range from 40…
Dielectric membranes with exceptional mechanical and optical properties present one of the most promising platforms in quantum opto-mechanics. The performance of stressed silicon nitride nanomembranes as mechanical resonators notoriously…
In this work, we have studied the phonon properties of multi-layered graphene with the use of Molecular Dynamics (MD) simulations and the k-space Autocorrelation Sequence (k-VACS) method. We calculate the phonon dispersion curves, densities…
The quasiparticle relaxation dynamics of the iron-based superconductor CsCa$_2$Fe$_4$As$_4$F$_2$ ($T_c$ $\sim$ 29 K) were investigated using ultrafast optical spectroscopy. A pseudogap ($\Delta_{PG}$ $\approx$ 3.3 meV) was observed to open…
The caged compound LaRu2Zn20 exhibits a structural transition at TS =150 K, whose driving mechanism remains elusive. We have investigated atomic dynamics by the measurements of specific heat C and inelastic X-ray scattering (IXS). The…
Two-dimensional system of the fermions with the indirect Einstein phonon-exchange attraction and added local four-fermion interaction is considered. It is shown that in such a system at resulting attraction between particles a new…
Phonon transmission across epitaxial interfaces is studied within the lattice dynamic approach. The transmission shows weak dependence on frequency for the lattice wave with a fixed angle of incidence. The dependence on azimuth angle is…
We investigated the photoexcited carrier dynamics in Si by using optical pump and terahertz probe spectroscopy in an energy range between 2 meV and 25 meV. The formation dynamics of excitons from unbound e-h pairs was studied through the…
Up to two layers of epitaxial graphene have been grown on the Si-face of two-inch SiC wafers exhibiting room-temperature Hall mobilities up to 1800 cm^2/Vs, measured from ungated, large, 160 micron x 200 micron Hall bars, and up to 4000…
The coherent folded longitudinal acoustic phonons (FLAPs) in gold nanoparticles (NPs) imbedded InGaN/GaN sample have been studied using degenerate pump-probe technique. When the FLAPs are generated within the multiple quantum wells, the…
We report the first fully self-consistent calculations of the nonlinear optical properties of superlattices. The materials investigated are mono-layer superlattices with GaP grown on the the top of InP, AlP and GaAs (110) substrates. We use…
A high-frequency optical phonon mode of SrTiO3 (STO) was found to assist the high-temperature superconductivity observed recently at the interface between monolayer FeSe and STO substrate. However, the origin of this mode is not clear.…
The recent discovery of 2D superconductivity at the interface of BaPbO$_3$ (BPO) and BaBiO$_3$ (BBO) has motivated us to study in depth the electronic and structural properties and the relation between them in this particular…
Using finite temperature Raman spectroscopy, we investigate the electron-phonon interactions (EPI) and phonon-phonon scattering dynamics in the Dirac semimetal Cd3As2 in different fre quency regimes. Strong softening of the Raman shifts…
Probing phonons, quasi-particle excitations and their coupling has enriched our understanding of these 2D materials and proved to be crucial for developing their potential applications. Here, we report comprehensive temperature, 4-330 K,…