Europhys. Lett.
Volume 75, Number 1, July 2006
Page(s) 42 - 48
Section Electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics
Published online 09 June 2006
Europhys. Lett., 75 (1), pp. 42-48 (2006)
DOI: 10.1209/epl/i2006-10093-9

Heat conduction in 2d harmonic lattices with on-site potential

D. Barik

Indian Association for the Cultivation of Science - Jadavpur, Kolkata 700 032, India

received 1 February 2006; accepted in final form 16 May 2006
published online 9 June 2006

We discuss heat conduction in 2d lattices, the first example of a class of 2d harmonic crystals subject to on-site anharmonic potentials. In general, they do not show up linear thermal gradient in contrast to their 1d counterparts. Inclusion of specific nonlinearity, however, leads to conductivity which diverges logarithmically with system size. The variation of thermal conductivity ($\kappa$) with temperature and dissipation enables us to identify a dynamical contribution over and above the thermodynamic factor allowed by the transition state theory as $\kappa=\kappa_{dynamic}\times \kappa_{thermodynamic}$ and to distinguish the regimes of energy diffusion and spatial diffusion in the nonequilibrium stationary state in thermal conduction.

44.10.+i - Heat conduction.
05.40.-a - Fluctuation phenomena, random processes, noise, and Brownian motion.
05.60.-k - Transport processes.

© EDP Sciences 2006