arXiv subjects

A. Schenkel

Publications and source records attributed to A. Schenkel.

2 recordsLinked to original sources

arXiv2005

Normal Heat Conductivity in a strongly pinned chain of anharmonic oscillators

We consider a chain of coupled and strongly pinned anharmonic oscillators subject to a non-equilibrium random forcing. Assuming that the stationary state is approximately Gaussian, we first derive a stationary Boltzmann equation. By localizing the involved resonances, we next invert the linearized collision operator and compute the heat conductivity. In particular, we show that the Gaussian approximation yields a finite conductivity $κ\sim\frac{1}{λ^2T^2}$, for $λ$ the anharmonic coupling strength.

cond-mat.stat-mech↗

arXiv2003

Perturbative analysis of anharmonic chains of oscillators out of equilibrium

We compute the first-order correction to the correlation functions of the stationary state of a stochastically forced harmonic chain out of equilibrium when a small on-site anharmonic potential is added. This is achieved by deriving a suitable formula for the covariance matrix of the invariant state. We find that the first-order correction of the heat current does not depend on the size of the system. Second, the temperature profile is linear when the harmonic part of the on-site potential is zero. The sign of the gradient of the profile, however, is opposite to the sign of the temperature difference of the two heat baths.

math-ph↗