Three universality classes for reaction fronts in disordered flows
Séverine Atis1, Awadhesh Kumar Dubey1, Dominique Salin1, Laurent Talon1, Pierre Le Doussal2, Kay Jörg Wiese2
1
FAST, CNRS, UPSud, UPMC, UMR 7608, Batiment 502, Campus Universitaire, 91405 Orsay, France.
2 CNRS-Laboratoire de Physique Théorique de
l'Ecole Normale Supérieure,
24 rue Lhomond, 75005 Paris, France.
Abstract
Self-sustained reaction fronts in a disordered medium subject to an external flow display self-affine roughening, pinning and depinning transitions. We measure spatial and temporal fluctuations of the front in 1+1 dimensions, controlled by a single parameter, the mean flow velocity. Three distinct universality classes are observed, consistent with the Kardar-Parisi-Zhang (KPZ) class for fast advancing or receding fronts, the quenched KPZ class (positive-qKPZ) when the mean flow approximately cancels the reaction rate, and the negative-qKPZ class for slowly receding fronts. Both quenched KPZ classes exhibit distinct depinning transitions, in agreement with the theory.
arXiv:1410.1097 [pdf]
Phys. Rev. Lett. 114 (2015) 234502 [pdf]
Copyright (C) by Kay Wiese. Last edited April 23, 2015.