Heat conduction in one-dimensional oscillator lattices using Nosé–Hoover chain thermostats

Abstract

In this work, we numerically study the dynamical evolution and heat transport properties of a system that consists of two time-reversible thermostats connected either by a one-dimensional Fermi–Pasta–Ulam or a Frenkel–Kontorova oscillator lattice, which are representative models of momentum-conserving and nonconserving systems, respectively. The thermostats were described by a chain of variables, Nosé–Hoover chains, which enhances the ergodicity of the thermostats in comparison to the Nosé–Hoover method. The time evolution of both lattices is not significantly altered by the dynamics of the thermostats. The temperature profile and heat flux of the Fermi–Pasta–Ulam model are more sensitive to the dynamics of the extended variables than those corresponding to the Frenkel–Kontorova model. Nevertheless we reproduce the scaling properties of the thermal conductivity with system size obtained by other authors.