Weakly disordered absorbing-state phase transitions

TL;DR

This paper investigates how quenched disorder influences nonequilibrium phase transitions in the directed percolation class, revealing that even minimal disorder leads to critical behavior governed by an infinite-randomness fixed point, akin to random transverse-field Ising models.

Contribution

It demonstrates that quenched disorder causes directed percolation transitions to fall into an infinite-randomness universality class, using a strong-disorder renormalization group approach.

Findings

Disorder drives critical behavior to an infinite-randomness fixed point.

The universality class matches that of the random transverse-field Ising model.

Results are relevant for experimental systems with quenched disorder.

Abstract

The effects of quenched disorder on nonequilibrium phase transitions in the directed percolation universality class are revisited. Using a strong-disorder energy-space renormalization group, it is shown that for any amount of disorder the critical behavior is controlled by an infinite-randomness fixed point in the universality class of the random transverse-field Ising models. The experimental relevance of our results are discussed.