Related papers: A lower bound to the thermal diffusivity of insula…
High temperature thermal transport in insulators has been conjectured to be subject to a Planckian bound on the transport lifetime $\tau \gtrsim \tau_\text{Pl} \equiv \hbar/(k_B T)$, despite phonon dynamics being entirely classical at these…
Measurements of thermal diffusivity in several insulators have been shown to reach a Planckian bound on thermal transport that can be thought of as the limit of validity of semiclassical phonon scattering. Beyond this regime, the heat…
We present high-resolution thermal diffusivity measurements on several near optimally doped electron- and hole-doped cuprate systems in a temperature range that passes through the Mott-Ioffe-Regel limit, above which the quasiparticle…
The transparent semiconductor In$_{2}$O$_{3}$ is a technologically important material. It combines optical transparency in the visible frequency range and sizeable electric conductivity. We present a study of thermal conductivity of…
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,…
The relaxation of a spatially sinusoidal temperature perturbation in a dielectric crystal at a temperature comparable to or higher than the Debye temperature is investigated theoretically. We assume that most phonons contributing to the…
For $\beta$-$\mathrm{Ga_2O_3}$ only little information exist concerning the thermal properties, especially the thermal conductivity $\lambda$. Here, the thermal conductivity is measured by applying the electrical 3$\omega$-method on…
Crystals and glasses differ by the amplitude and the temperature dependence of their thermal conductivity. However, there are crystals known to display glass-like thermal conductivity. Here, we show that EuTiO$_3$, a quantum paraelectric…
The room temperature thermal diffusivity of high T$_c$ materials is dominated by phonons. This allows the scattering of phonons by electrons to be discerned. We argue that the measured strength of this scattering suggests a converse…
The thermal conductivities of beta-Ga2O3 single crystals along four different crystal directions were measured in the temperature range of 80-495K using the time domain thermoreflectance (TDTR) method. A large anisotropy was found. At room…
Crystalline solids are generally known as excellent heat conductors, amorphous materials or glasses as thermal insulators. It has thus come as a surprise that certain crystal structures defy this paradigm. A prominent example are type-I…
We present a detailed study of the charge transport, optical reflectivity, and thermal transport properties of n-type PbSe crystals. A strong scattering, mobility-limiting mechanism was revealed to be at play at temperatures above 500 K.…
The thermal properties of solids under nanoscale confinement are currently not understood at the atomic level. Recent numerical studies have highlighted the presence of a minimum in the thermal conductivity as a function of thickness for…
To elucidate the relationship between a crystal's structure, its thermal conductivity, and its phonon dispersion characteristics, an analysis is conducted on layered diatomic Lennard-Jones crystals with various mass ratios. Lattice dynamics…
We present a study of thermal conductivity, $\kappa$, in undoped and doped strontium titanate in a wide temperature range (2-400 K) and detecting different regimes of heat flow. In undoped SrTiO$_{3}$, $\kappa$ evolves faster than cubic…
It is textbookly regarded that phonons, i.e., an energy quantum of propagating lattice waves, are the main heat carriers in perfect crystals. As a result, in many crystals, e.g., bulk silicon, the temperature-dependent thermal conductivity…
The monoclinic crystal structure of $\beta$-$\mathrm{Ga_2O_3}$ leads to significant anisotropy of the thermal properties. The 2$\omega$-method is used to measure the thermal diffusivity $D$ in [010] and [001] direction respectively and to…
The low-temperature thermal properties of dielectric crystals are governed by acoustic excitations with large wavelengths that are well described by plane waves. This is the Debye model, which rests on the assumption that the medium is an…
Analyses of thermal diffusivity data on complex insulators and on strongly correlated electron systems hosted in similar complex crystal structures suggest that quantum chaos is a good description for thermalization processes in these…
By studying the temperature-dependent behavior of electron thermal conductivity (k) in a 3.2 nm-thin film, we quantify the extremely confined defect-electron scattering and reveal the intrinsic phonon-electron scattering that is shared by…