Related papers: Vibrational and thermoelastic properties of bcc ir…
The problem of acquiring elastic properties of a composite material from the data of the vibrational testing is considered. The specimen is considered to abide by the linear elasticity laws and subject to viscoelastic damping. The BVP for…
We present an alternative method for determining the sound velocity in atomic Bose-Einstein condensates, based on thermodynamic global variables. The total number of trapped atoms was as a function of temperature carefully studied across…
The unconventional thermal properties of jammed amorphous solids are directly related to their density of vibrational states. While the vibrational spectrum of jammed soft sphere solids has been fully described, the vibrational spectrum of…
Turbulence is a key process in many astrophysical systems. In this work we explore the statistics of thermal and kinetic energy of isothermal, supersonic, turbulent gas. We develop analytic formulas for the PDF of thermal and kinetic…
The thermoelectric properties of a molecular junction model, appropriate for large molecules such as fullerenes, are studied within a non-equilibrium adiabatic approach in the linear regime at room temperature. A self-consistent calculation…
Screw dislocations in bcc metals display non-planar cores at zero temperature which result in high lattice friction and thermally activated strain rate behavior. In bcc W, electronic structure molecular statics calculations reveal a…
Single crystal elastic constants of bcc iron and bct FeC and FeN alloys, martensites, have been evaluated by ab initio calculations based on the density functional theory. The energy of a strained crystal has been computed using the…
We report on a laser generated and detected surface acoustic wave method for evaluating the elastic constants of micro-crystals composing polycrystalline steel. The method is based on the measurement of surface wave velocities in many…
For a given crystal structure, say body-centred-cubic, the many-body Hamiltonian in which nuclear and electron motions are to be treated from the outset on the same footing, has parameters, for the elements, which can be classified as (i)…
Interatomic potentials approximate the potential energy of atoms as a function of their coordinates. Their main application is the effective simulation of many-atom systems. Here, we review empirical interatomic potentials designed to…
Silicon carbide, a semiconducting material, has gained importance in the fields of ceramics, electronics, and renewable energy due to its remarkable hardness and resistance. In this study, we delve into the impact of nuclear quantum motion,…
A combination of quantum mechanics calculations with machine learning (ML) techniques can lead to a paradigm shift in our ability to predict materials properties from first principles. Here we show that on-the-fly training of an interatomic…
Elastic constants are central material properties, frequently reported in experimental and theoretical studies. While their computation is straightforward in the absence of thermal fluctuations, finite--temperature methods often suffer from…
We compute the equilibrium crystal structure and phase stability of iron at the alpha(bcc)-gamma(fcc) phase transition as a function of temperature, by employing a combination of ab initio methods for calculating electronic band structures…
We have carried out boundary-layer-resolved, unstructured fully-compressible Navier--Stokes simulations of an ultrasonic standing-wave thermoacoustic engine (TAE) model. The model is constructed as a quarter-wavelength engine, approximately…
We present measurements of the dynamical response of thermal noise to an ac excitation in conductors at low temperature. From the frequency dependence of this response function - the noise thermal impedance - in the range 1 kHz-1 GHz we…
An important goal in nanoelectromechanics is to cool the vibrational motion, ideally to its quantum ground state. Cooling by an applied charge current is a particularly simple and hence attractive strategy to this effect. Here, we explore…
An analytical solution has been developed clarifying that the thermally driven elastic softening of crystals can be directly related to the length and strength of the representative bonds of the crystal and to the response of the bonding…
To analyze nonidealities inherent to degenerate plasma, a quantum collective approach is developed. Thermodynamic functions of a system of partially degenerate electrons and strongly coupled ions are derived from first principles. The model…
We present the detailed study of the thermodynamics of vibrational modes in disordered elastic systems such as the Bragg glass phase of lattices pinned by quenched impurities. Our study and our results are valid within the (mean field)…