Computer simulation study of thermal conduction in 1d chains of anharmonic oscillators

Abstract

In this work thermal conduction in one-dimensional (1D) chains of anharmonic oscillators are studied using computer simulation. The temperature profile, heat flux and thermal conductivity are investigated for chain length N = 100, 200, 400, 800 and 1600. In the computer simulation anharmonicity is introduced due to Fermi-Pasta-Ulam-β (FPU-β) model. For substrate interaction, an onsite potential due to Frenkel-Kontorova (FK) model has been used. Numerical simulations demonstrate that temperature gradient scales behave as N-1 linearly with the relation J = 0.1765/N. For the thermal conductivity K, KN to N obey the linear relation of the type KN = 0.8805N. It is shown that thermal transport is dependent on phonon-phonon interaction as well as phonon-lattice interaction. The thermal conductivity increases linearly with increase inanharmonicity and predicts relation κ = 0.133 + 0.804β. It is also concluded that for higher value of the strength of the onsite potential system tends to a thermal insulator. © 2013 Chinese Physical Society and IOP Publishing Ltd.