Crystallization of hard disks induced by a temperature gradient
S. Wołoszczuk1 , A. Lipowski1
1 Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61-614, Poznan, Poland
Phys Rev E, 81, 061132 (2010)
While uniform temperature has no effect on equilibrium properties of hard-core systems, its gradient might substantially change their behaviour. In particular, in hard-disk system subject to temperature difference ΔT disks are repelled from the hot boundary of the system and accumulate at the cold one. Using event-driven molecular dynamics simulations we show that for sufficiently large ΔT or coverage ratio ρ*, crystal forms at the cold boundary. In this spatially inhomogeneous system a significant decrease of diffusivity of disks clearly marks the stationary interface between liquid and crystal. Such a behaviour is also supported through calculation of the radial distribution function and the bond order parameter. Simulations show that for this nonequilibrium system the equipartition of energy holds and velocity obeys the Boltzmann distribution.