Nonuniversal heat conduction of one-dimensional lattices.

For one-dimensional nonlinear lattices with momentum conserving interparticle interactions, intensive studies have suggested that the heat conductivity κ diverges with the system size L as κ~L(α) and the value of α is universal. But in the Fermi-Pasta-Ulam-β lattices with nearest-neighbor (NN) and next-nearest-neighbor (NNN) coupling, we find that α strongly depends on γ, the ratio of the NNN coupling to the NN coupling. The correlation between the γ-dependent heat conduction behavior and the in-band discrete breathers is also analyzed.