Abstract

We study the nonequilibrium phase transition in the one-dimensional contact process with quenched spatial disorder by means of large-scale Monte Carlo simulations for times up to 109 and system sizes up to 107 sites. In agreement with recent predictions of an infinite-randomness fixed point, our simulations demonstrate activated (exponential) dynamical scaling at the critical point. The critical behavior turns out to be universal, even for weak disorder. However, the approach to this asymptotic behavior is extremely slow, with crossover times of the order of 104 or larger. In the Griffiths region between the clean and the dirty critical points, we find power-law dynamical behavior with continuously varying exponents. We discuss the generality of our findings and relate them to a broader theory of rare region effects at phase transitions with quenched disorder.

Department(s)

Physics

Sponsor(s)

National Science Foundation (U.S.)
Research Corporation
University of Missouri Research Board

Keywords and Phrases

Monte Carlo method; Phase transformations (Statistical physics)

Document Type

Article - Journal

Document Version

Final Version

File Type

text

Language(s)

English

Rights

© 2005 American Physical Society (APS), All rights reserved.

Included in

Physics Commons

Share

 
COinS