Related papers: Maximizing phonon thermal conductance for ballisti…
Tailored magnon-phonon hybrid systems, where high overtone bulk acoustic resonators couple resonantly to the magnonic mode of a ferromagnetic thin film, are considered optimal for the creation of acoustic phonons with a defined circular…
We systematically demonstrate the temperature-dependent thermal transport properties in crystalline Ge$_2$Sb$_2$Te$_5$via first-principles density functional theory-informed linearized Boltzmann transport equation. The investigation,…
We present atomistic valence force field calculations of thermal transport in Si nanowires of diameters from 12nm down to 1nm. We show that as the diameter is reduced, the phonon density-of-states and transmission function acquire a finite…
Many complex crystals show a flattening or even increasing lattice thermal conductivity at high temperatures, which deviates from the traditional 1/T decay trend given by conventional phonon theory. In this work, we predict the thermal…
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…
Layered two-dimensional (2D) materials have highly anisotropic thermal properties between the in-plane and cross-plane directions. In general, it is thought that cross-plane thermal conductivities ($\kappa_z$) are low, and therefore c-axis…
Multiwalled carbon nanotubes are shown to be ballistic conductors at room temperature, with mean free paths of the order of tens of microns. These experiments follow and extend the original experiments by Frank et al (Science, 280 1744…
We have performed thermal conductance measurements on individual single crystalline silicon suspended nanowires. The nanowires (130 nm thick and 200 nm wide) are fabricated by e-beam lithography and suspended between two separated pads on…
We have studied the effects of phonon-boundary scattering on the thermal transport in topological Kondo insulator, SmB$_6$. The studies have been performed by using the $3\omega$ method in the temperature range 300K - 3K. We show that the…
The experimentally observed order-of-magnitude reduction in the thermal conductivity along the growth axis of (GaAs)_n/(AlAs)_n (or n x n) superlattices is investigated theoretically for (2x2), (3x3) and (6x6) structures using an accurate…
Elastic wave characteristics of the heat conduction in low-temperature thin wires can be studied via a wave scattering formalism. A reaction matrix formulation of heat conductance modeled by elastic wave scattering is advocated. This…
Developing simplified, but accurate, theoretical approaches to treat heat transport on all length and time scales is needed to further enable scientific insight and technology innovation. Using a simplified form of the Boltzmann transport…
Understanding heat transport in organic semiconductors is of fundamental and practical relevance. Therefore, we study the lattice thermal conductivities of a series of (oligo)acenes, where an increasing number of rings per molecule leads to…
Suppressing phonon propagation in nanowires is an essential goal towards achieving efficient thermoelectric devices. Recent experiments have shown unambiguously that surface roughness is a key factor that can reduce the thermal conductivity…
We outline a general approach to the computation of transport properties of interacting systems at low temperetures and frequencies. We show that if the fixed point and the irrelevant operators around it are known, then by studying the…
The phonon thermal transport properties of twisted bi-layer graphene are investigated using lattice dynamics and the Boltzmann transport equation. The thermal conductivities of 13.2 and 21.8 twisted configurations are 56% and 36% lower than…
Nanostructuring on length scales corresponding to phonon mean free paths provides control over heat flow in semiconductors and makes it possible to engineer their thermal properties. However, the influence of boundaries limits the validity…
Understanding the thermal properties of two-dimensional (2D) materials and devices is essential for thermal management of 2D applications. Here we perform molecular dynamics simulations to evaluate both the specific heat of $MoS_{2}$ as…
Periodic hole array phononic crystals (PnC) can strongly modify the phonon dispersion relations, and have been shown to influence thermal conductance coherently, especially at low temperatures where scattering is suppressed. One very…
Tailoring thermal properties with nanostructured materials can be of vital importance for many applications. Generally classical phonon size effects are employed to reduce the thermal conductivity, where strong phonon scattering by…