Effect of phonon-phonon interactions on localization.
We study the heat current J in a classical one-dimensional disordered chain with on-site pinning and with ends connected to stochastic thermal reservoirs at different temperatures. In the absence of anharmonicity all modes are localized and there is a gap in the spectrum. Consequently J decays exponentially with system size N. Using simulations we find that even a small amount of anharmonicity leads to a J approximately 1/N dependence, implying diffusive transport of energy.
Raman Research Institute, Bangalore 560080, India.
Abhishek
A
Dhar
J L
JL
Lebowitz