Related papers: Anharmonic effects in atomic hydrogen: superconduc…
Generalized theory of the normal properties of the metal in the case of the electron-phonon (EP) systems with not constant density of electronic states is used to examine the normal state of the SH3 and SH2 phase of the hydrogen sulfide at…
Inelastic neutron scattering measurements on silver oxide (Ag$_2$O) with the cuprite structure were performed at temperatures from 40 to 400\,K, and Fourier transform far-infrared spectra were measured from 100 to 300\,K. The measured…
Isotopic effects are relevant to understand several properties of solids, and have been thoroughly analyzed along the years. These effects may depend on the dimensionality of the considered solid. Here we assess their magnitude for…
Understanding electrical resistivity in metals remains a central challenge in quantifying charge transport at finite temperature. Current first-principles calculations based on the Boltzmann transport equation often match experiments, yet…
Phonon spectrum of many superconducting compounds and, especially, high Tc hydrides, is broad and rather complicated ,because of presence of high frequency optical modes. In order to analyze an interplay of optical and acoustic phonon…
Despite the widespread use of silicon in modern technology, its peculiar thermal expansion is not well-understood. Adapting harmonic phonons to the specific volume at temperature, the quasiharmonic approximation, has become accepted for…
Many complex intermetallic structures possess cage-like environments that can host additional guest atoms. In Al$_{10}$V, these atoms give rise to low-frequency, localized vibrations (Einstein modes) that dominate the thermodynamic response…
Liquid drops and vibrations are ubiquitous in both everyday life and technology, and their combination can often result in fascinating physical phenomena opening up intriguing opportunities for practical applications in biology, medicine,…
We present results predicting experimentally measurable structural quantities from molecular dynamics studies of hydrogen. In doing this, we propose a paradigm shift for experimentalists -- that the predictions from such calculations should…
We study the electron-acoustic instabilities in plasmas with two kappa-distributed electrons and stationary ions. The instabilities are driven by the relative drift between two electron components. The suprathermal effects of different…
The nature of the lattice instability connected to the structural transition and superconductivity of (Sr,Ca)$_3$Ir$_4$Sn$_{13}$ is not yet fully understood. In this work density functional theory (DFT) calculations of the phonon…
A systematic Raman study in the visible carried out on the YBa2Cu316,18Ox (x=6-7) compounds, with isotopic substitution of 18O for 16O, has detected a doping dependent deviation from harmonic behavior for the frequency shift of the in-phase…
We obtain a rigorous upper bound on the resistivity $\rho$ of an electron fluid whose electronic mean free path is short compared to the scale of spatial inhomogeneities. When such a hydrodynamic electron fluid supports a non-thermal…
Hydrogen is the most abundant element in the universe, and its properties under conditions of high temperature and pressure are crucial to understand the interior of of large gaseous planets and other astrophysical bodies. At ultra high…
Superconductivity in compressed H3S arises from the interplay between high-frequency phonons and a pronounced van Hove singularity near the Fermi level. Using first-principles calculations, we investigate the superconducting properties of…
The crystal structure and electrical resistance of the structurally-layered EuFe2As2 have been studied up to 70 GPa and down to temperature of 10 K, using a synchrotron x-ray source and the designer diamond anvils. The room-temperature…
Slow dynamics of energy transfer between different phonon modes under the resonance conditions is considered. It may result in new effects in the inelastic and quasielastic neutron scattering spectra.
Thermal transport in crystals is influenced by chemistry, boundaries, and nanostructure. The anharmonic phonon band structure extracted from molecular-dynamics simulations provides an illuminating view of both the type and extent of…
The Coulomb repulsion between ions in a linear Paul trap give rise to anharmonic terms in the potential energy when expanded about the equilibrium positions. We examine the effect of these anharmonic terms on the accuracy of a quantum…
We study the effects of anharmonicity on the physics of the Holstein model, which describes the coupling of itinerant fermions and localized quantum phonons, by introducing a quartic term in the phonon potential energy. We find that the…