https://doi.org/10.1140/epjst/e2007-00364-7
Anomalous transport and relaxation in classical one-dimensional models
1
Dipartimento di Matematica, Università di Firenze, viale Morgagni 67a, 50134 Firenze, Italy
2
Istituto dei Sistemi Complessi, Consiglio Nazionale delle Ricerche, via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy
3
Dipartimento di Fisica, via G. Sansone 1, 50019 Sesto Fiorentino, Italy
4
Ceremade, UMR-CNRS 7534, Université de Paris Dauphine, 75775 Paris Cedex 16, France
Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.
Abstract
After reviewing the main features of anomalous energy transport in 1D systems, we report simulations performed with chains of noisy anharmonic oscillators. The stochastic terms are added in such a way to conserve total energy and momentum, thus keeping the basic hydrodynamic features of these models. The addition of this “conservative noise" allows to obtain a more efficient estimate of the power-law divergence of heat conductivity κ(L) ∼Lα in the limit of small noise and large system size L. By comparing the numerical results with rigorous predictions obtained for the harmonic chain, we show how finite-size and time effects can be effectively controlled. For low noise amplitudes, the α values are close to 1/3 for asymmetric potentials and to 0.4 for symmetric ones. These results support the previously conjectured two-universality-classes scenario.
© EDP Sciences, Springer-Verlag, 2007
