Identifying diffusion processes in one-dimensional lattices in thermal equilibrium
- 物理技术－已发表论文 
In this Letter, I propose that a properly rescaled spatiotemporal correlation function of the energy density fluctuations may be applied to characterize the equilibrium diffusion processes in lattice systems with finite temperature. Applying this function, the diffusion processes in three one-dimensional nonlinear lattices are studied. The diffusion exponent alpha is shown to be related to the diverging exponent gamma of the thermal conductivity of a lattice through the relation gamma=alpha-1, as has been proved based on the Levy walk assumption. The diffusion behavior is explained in terms of solitons and phonons.