We study the nonequilibrium state of heat conduction in a one-dimensional system of hard point particles of unequal masses interacting through elastic collisions. A BBGKY-type formulation is presented and some exact results are obtained from it. Extensive numerical simulations for the two-mass problem indicate that, even for arbitrarily small mass differences, a nontrivial steady state is obtai...

We report the first experimental results on the temperature dependent in-plane and cross-plane thermal conductivities of a symmetrically strained Si/Ge superlattice and a Ge quantum-dot superlattice measured by the two-wire 3 omega method. The measured thermal conductivity values are highly anisotropic and are significantly reduced compared to the bulk thermal conductivity of the structures. Th...

The resistance of metals is a function of applied pressure, and this dependence is large enough to be significant in the calibration of transient hot-wire thermal conductivity instruments. We recommend that for the highest possible accuracy, the instrument's hot wires should be calibrated in situ. If this is not possible, we recommend that a value of γ, the relative resistance change with press...

New experimental data on the thermal conductivity of 2,3,3,3-tetrafluoroprop-1-ene (R1234yf) and trans-1,3,3, 3-tetrafluoropropene (R1234ze(E)) are reported that allow the development of wide-range correlations. These new experimental data, covering a temperature range of (242 to 344) K for R1234yf and (203 to 344) K for R1234ze(E) at a pressure range of (0.1 to 23) MPa, are used to develop cor...

In one and two dimensions, transport coefficients may diverge in the thermodynamic limit due to long-time correlation of the corresponding currents. The effective asymptotic behavior is addressed with reference to the problem of heat transport in one-dimensional crystals, modeled by chains of classical nonlinear oscillators. Extensive accurate equilibrium and nonequilibrium numerical simulation...

The equivalence between a noise source in combination with a resistance, and a thermal bath, is a part of fluctuation theory. This observation was the motivation for the author’s 1960 calculation of the power flow between modes of vibration excited by random noise sources. The resulting relation between power flow and uncoupled energy of vibration is therefore more than a thermal analogy; it is...

We analyze the thermal conductivity of frustrated spin-1/2 chains within linear-response theory focusing on its frequency dependence at finite temperatures. Using exact diagonalization, the low-frequency limit of the thermal conductivity is discussed in the high-temperature regime.

The geothermal heat flux is a critical thermal boundary condition that influences the melting, flow, and mass balance of ice sheets, but measurements of this parameter are difficult to make in ice-covered regions. We report the first direct measurement of geothermal heat flux into the base of the West Antarctic Ice Sheet (WAIS), below Subglacial Lake Whillans, determined from the thermal gradie...

Abstract. Climate is usually considered to depend on a large number of parameters, this being essentially a functional in multi-dimensional parameter space. We propose a low-dimensional model of a climate where the temperature field on a thermally conducting planet depends on the external energy input and very limited number of internal parameters, like thermal conductivity and reflectivity. Eq...

We report on the out-of-plane thermal conductivities of epitaxial Fe3O4 thin films with thicknesses of 100, 300, and 400 nm, prepared using pulsed laser deposition (PLD) on SiO2/Si substrates. The four-point probe three-omega (3-ω) method was used for thermal conductivity measurements of the Fe3O4 thin films in the temperature range of 20 to 300 K. By measuring the temperature-dependent thermal...