Related papers: Phonon thermal transport in UO$_2$ via self-consis…
Modeling the high-$T$ paramagnetic state of bulk UO$_2$ by a non-spin-polarized calculation and neglecting the Hubbard-U correction for the $f$ electrons in U atoms, the lattice thermal conductivity of bulk UO$_2$ is investigated by the…
Defects can significantly degrade the thermal conductivity of ThO2, an advanced nuclear fuel material as well as a surrogate for other fluorite-structured materials. We investigate how point defects in ThO2 impact phonon mode-resolved…
We report first-principles calculations of the phonon dispersion spectrum, thermal expansion, and heat capacity of uranium dioxide. The so-called direct method, based on the quasiharmonic approximation, is used to calculate the phonon…
Understanding thermal transport in 2D materials and especially in graphene is a key challenge for the design of heat management and energy conversion devices. The high sensitivity of measured transport properties to structural defects,…
Thermal transport in the Si/SiO$_2$ multishell nanotubes is investigated theoretically. The phonon energy spectra are obtained using the atomistic Lattice Dynamics approach. Thermal conductivity is calculated using the Boltzmann transport…
This work demonstrates a first-principles-based approach to obtaining finite temperature thermal and electronic transport properties which can be employed to model and understand mesoscale structural evolution during electronic, magnetic,…
Uranium dioxide (UO$_2$), one of the most important nuclear fuels, can accumulate excess oxygen atoms as interstitial defects, which significantly impacts thermal properties. In this study, thermal conductivities and inelastic neutron…
A discovery of the unusual thermal properties of graphene stimulated experimental, theoretical and computational research directed at understanding phonon transport and thermal conduction in two-dimensional material systems. We provide a…
Many crystals, such as lanthanum zirconate (La2Zr2O7), exhibit a flat temperature dependence of thermal conductivity at elevated temperatures. This phenomenon has recently been attributed to the inter-band phonon tunneling (or diffuson)…
The lattice thermal conductivity of graphene is evaluated using a microscopic model that takes into account the lattice's discrete nature and the phonon dispersion relation within the Brillouin zone. The Boltzmann transport equation is…
Lattice thermal conductivities of two SiO$_2$ polymorphs, i.e., $\alpha$-quartz (low) and $\alpha$-cristobalite (low), were studied using first-principles anharmonic phonon calculation and linearized phonon Boltzmann transport equation.…
Phonon lifetimes are a key component of quasiparticle theories of transport, yet first-principles lifetimes are rarely directly compared to inelastic neutron scattering (INS) results. Existing comparisons show discrepancies even at…
We study the quantum thermal transport of elastic excitations through a two-dimensional elastic waveguide between two thermal reservoirs. We solve the classical Kirchhoff-Love equation for rectangular wires and explore the dispersion…
We study coherent transport through a double quantum dot. Its two electronic leads induce electronic matter and energy transport and a phonon reservoir contributes further energy exchanges. By treating the system-lead couplings…
SrTiO$_3$ has been extensively investigated owing to its abundant degrees of freedom for modulation. However, the microscopic mechanism of thermal transport especially the relationship between phonon scattering and lattice distortion during…
Starting from our previous work where we have obtained a system of coupled integro-differential equations for acoustic sound waves and phonon density fluctuations in 2D crystals, we derive here the corresponding hydrodynamic equations and…
We investigate phonon transport in perovskite strontium titanate (SrTiO3) which is stable above its phase transition temperature (~105 K) by using first-principles molecular dynamics and anharmonic lattice dynamics. Unlike conventional…
Phonon transport across a vacuum gap separating intrinsic silicon crystals is predicted via the atomistic Green's function method combined with first-principles calculations of all interatomic force constants. The overlap of electron wave…
We study phonon transport in junctions of two harmonic reservoirs coupled together by a spring. The exact steady-state heat currents and thermal conductance are calculated using nonequilibrium Green's functions. We find that the heat…
We study ballistic interfacial thermal transport across atomic junctions. Exact expressions for phonon transmission coefficients are derived for thermal transport in one-junction and two-junction chains, and verified by numerical…