相关论文: Heat capacity of suspended phonon cavities
Specific heat of phonon cavities is investigated in order to analyse the effect of phonon confinement on thermodynamic properties. The specific heat of free standing very thin SiN membranes in the low dimensional limit is measured down to…
Modeling the heat capacity of liquids present fundamental difficulties due to the strong intermolecular particle interactions and large diffusive-like displacements. Based on the experimental evidence that the microscopic dynamics of…
Recent research shows that liquids and dense supercritical fluids support high frequency shear waves. Here, we proposed a general heat capacity model of supercritical fluids using the latest theoretical findings (the liquid phonon theory).…
The features of phonon spectra and their effect on the vibrational heat capacity of linear chains of inert gas atoms adsorbed onto a substrate, which is the surface of nanotubes bound to a nanobundle. The influence of the substrate results…
We experimentally study for the first time the self-heating normal domain in magnetic field using nanowires made of granular NbTiN films with sub-10~nm thicknesses. Specifically, we found that at temperatures below 10 K, the heat capacity…
At low temperatures, the thermal wavelength of acoustic phonons in a metallic thin film on a substrate can widely exceed the film thickness. It is thus generally believed that a mesoscopic device operating at low temperature does not carry…
We analyze the heat power $P$ between electrons and phonons in thin metallic films deposited on free-standing dielectric membranes in a temperature range in which the phonon gas has a quasi two-dimensional distribution. The quantization of…
The specific heat of expanded graphite (EG) and EG--multiwalled carbon nanotube (MWCNT) composites (1.0 and 3.0 wt.\% MWCNTs) was measured between 2 and 300~K. The low-temperature heat capacity is dominated by out-of-plane flexural phonons…
Phonon modes and their dispersion relations in ultrathin homogenous dielectric membranes are calculated using elasticity theory. The approach differs from the previous ones by a rigorous account of the effect of the film surfaces on the…
Recently there have been significant theoretical advances in our understanding of liquids and dense supercritical fluids based on their ability to support high frequency transverse (shear) waves. Here, we have constructed a new computer…
We discuss computational analysis of phononic thermal conduction in the suspended membrane geometry, in the experimentally commonly appearing case where heat can flow out radially in two dimensions from a central source. As we are mostly…
Classical thermal transport theories that preserve rotational symmetry, predict strong anharmonic scattering of out-of-plane lattice vibrational modes called flexural phonons in flat suspended graphene sheets. Such strong scattering…
Recent theory has predicted large temperature differences between the in-plane (LA and TA) and out-of-plane (ZA) acoustic phonon baths in locally-heated suspended graphene. To verify these predictions, and their implications for…
We report the observation of an unexpected quadratic temperature dependence of the heat capacity in the vanadium sulphide metal V5S8 at low temperatures which is independent of applied magnetic field. We find that the behaviour of the heat…
Heat transport in bulk materials is well described using the Debye theory of 3D vibrational modes (phonons) and the acoustic match model. However, in cryogenic nanodevices, phonon wavelengths exceed device dimensions, leading to confinement…
We examine the hydrodynamic phonon spectrum of a monolayer film adsorbed on the wall of a spherical pore. Due to the boundary conditions, the monolayer film exhibits a discrete phonon spectrum. The corresponding density of states per unit…
Self-heating normal domains in thin superconducting NbTiN nanostrips were characterized via steady-state hysteretic current-voltage characteristics measured at different substrate temperatures. The temperature dependence and the magnitude…
Fractionalized excitations are of considerable interest in recent condensed-matter physics. Fractionalization of the spin degrees of freedom into localized and itinerant Majorana fermions are predicted for the Kitaev spin liquid, an exactly…
In recent decades, the laws of thermodynamics have been pushed down to smaller and smaller scales, within the field of stochastic thermodynamics and state-of-art experiments performed on mesoscopic systems. These measurements concern…
We present an analysis of acoustic phonon propagation through long, free-standing, insulating wires with rough surfaces. Due to a crossover from ballistic propagation of the lowest-frequency phonon mode at $\omega <\omega _{1}=\pi c/W$ to a…