Two-species reaction-diffusion system with equal diffusion constants: anomalous density decay at large times
We study a two-species reaction-diffusion model where A+A-->, A+B-->, and B+B-->, with annihilation rates lambda(0), delta(0)>lambda(0), and lambda(0), respectively. The initial particle configuration is taken to be randomly mixed with mean densities n(A)(0)>n(B)(0), and with the two species A and B diffusing with the same diffusion constant. A field-theoretic renormalization group analysis suggests that, contrary to expectation, the large-time density of the minority species decays at the same rate as the majority when d</=2. Monte Carlo data support the field theory prediction in d=1, while in d=2 the logarithmically slow convergence to the large-time asymptotics makes a numerical test difficult.
Konkoli
Z
NORDITA, Blegdamsvej 17, DK 2100 Kobenhavn, Denmark and Institute of Theoretical Physics, Chalmers University of Technology and Goteborg University, SE 412 96 Goteborg, Sweden.
Johannesson
H