Related papers: Transient hydrodynamic phonon transport in two-dim…
The properties of two-dimensional (2D) materials have been extensively studied and applied in various applications. Our interest is to theoretically investigate the thermal transport and thermoelectric properties of the 2D transition metal…
ErTe$_3$ is studied as a model system to explore thermal transport in a layered charge density wave (CDW) material. We present data from thermal diffusivity, resistivity, and specific heat measurements: There is a sharp decrease in thermal…
The propagation of second sound, and more broadly the ballistic transport of heat, is of central importance in heat dissipation from electronic devices at very short length and time scales. Specifically, there is an interest in the…
Understanding the dynamics of photoexcited carriers is essential for advancing photoelectronic device design. Photon absorption generates electron-hole pairs, and subsequent scatterings can induce ultrafast thermalization within a…
Phonon scattering by electrons, or "phonon-electron scattering", has been recognized as a significant scattering channel for phonons in materials with high electron concentration, such as thermoelectrics and nanoelectronics, even at room…
The subject of thermal transport at the mesoscopic scale and in low-dimensional systems is interesting for both fundamental research and practical applications. As the first example of truly two-dimensional materials, graphene has…
The infrared reflectance of the transition metal chalcogenide 1T-TaS2 has been measured at temperatures from 30K to 360K over 30-45,000cm^-1 (4meV-5.5eV). The optical conductivity was obtained by Kramers-Kronig analysis. At 360K only modest…
We present an ab-initio study of photocarrier dynamics in graphene due to electron-phonon (EP) interactions. Using the Boltzmann relaxation-time approximation with parameters determined from density functional theory (DFT) and a…
Thermoelectric effects allow the generation of electrical power from waste heat and the electrical control of cooling and heating. Remarkably, these effects are also highly sensitive to the asymmetry in the density of states around the…
We demonstrate electronic cooling of 1D phonon modes in suspended nanowires for the first time, using normal metal--insulator--superconductor (NIS) tunnel junctions. Simultaneous cooling of both electrons and phonons to a common temperature…
In this work, we report on hot carrier diffusion in graphene across large enough length scales that the carriers are not thermalized across the crystal. The carriers are injected into graphene at one site and their thermal transport is…
We employ dual-gated 30{\deg}-twisted bilayer graphene to demonstrate simultaneous ultra-high mobility and conductivity (up to 40 mS at room temperature), unattainable in a single-layer of graphene. We find quantitative agreement with a…
Thermal transport by phonons in films with thicknesses of less than 10 nm is investigated in a soft system (Lennard-Jones argon) and a stiff system (Tersoff silicon) using two-dimensional lattice dynamics calculations and the Boltzmann…
We report the first temperature dependent phonon transport measurements in suspended Cu-CVD single layer graphene (SLG) from 15K to 380K using microfabricated suspended devices. The thermal conductance per unit cross section $\sigma$/A…
We present a density functional perturbation theory approach to estimate the transition temperature of the charge density wave transition of TiSe2. The softening of the phonon mode at the L-point where in TiSe2 a giant Kohn anomaly occurs,…
In this study, we calculate the $T$=300 K scattering and thermoelectric transport properties of rhombohedral GeTe using first-principles modeling. The room-temperature phase of GeTe has a layered structure, with cross-plane and in-plane…
We investigate the microscopic mechanism of ultralow lattice thermal conductivity ($\kappa_l$) of TlInTe$_2$ and its weak temperature dependence using a unified theory of lattice heat transport that considers contributions arising from the…
The transport relaxation rate 1/tau of a two-dimensional electron gas due to scattering by thermally excited surface acoustic phonons is calculated. The temperature dependence of 1/tau is found to be linear in T for high temperatures, but…
This work establishes a closed-form analysis for two-dimensional transient heat transfer in an absorber plate based on the thermal wave model when the collector starts to work. The method of separation of variables is employed to determine…
To explore the thermal and thermoelectric potential of 2D materials, we study the h-NbN monolayer, which lacks mirror symmetry and features a large acoustic-optical phonon gap and quadratic flexural mode. First-principles calculations and…