2001/09/30 by Jae Dong Noh, Hyunggyu Park
Physics and Astronomy · #cond-mat.stat-mech
paper · pdf · doi:10.1103/physreve.69.016122
published as Phys. Rev. E 69, 016122 (2004) · 13 pages + 10 figures (Full paper version)
arxiv created 2002/12/02 · arxiv updated 2009/11/30
The well-established universality classes of absorbing critical phenomena are directed percolation (DP) and directed Ising (DI) classes. Recently, the pair contact process with diffusion (PCPD) has been investigated extensively and claimed to exhibit a new type of critical phenomena distinct from both DP and DI classes. Noticing that the PCPD possesses a long-term memory effect, we introduce a generalized version of the PCPD (GPCPD) with a parameter controlling the memory effect. The GPCPD connects the DP fixed point to the PCPD point continuously. Monte Carlo simulations show that the GPCPD displays novel type critical phenomena which are characterized by continuously varying critical exponents. The same critical behaviors are also observed in models where two species of particles are coupled cyclically. We suggest that the long-term memory may serve as a marginal perturbation to the ordinary DP fixed point.