title: Universal Long Ranged Correlations in Driven Binary Mixtures.
abstract: When two populations of "particles" move in opposite directions, like oppositely charged colloids under an electric field or intersecting flows of pedestrians, they can move collectively, forming lanes along their direction of motion. The nature of this "laning transition" is still being debated and, in particular, the pair correlation functions, which are the key observables to quantify this phenomenon, have not been characterized yet. Here, we determine the correlations using an analytical approach based on a linearization of the stochastic equations for the density fields, which is valid for dense systems of soft particles. We find that the correlations decay algebraically along the direction of motion, and have a self-similar exponential profile in the transverse direction. Brownian dynamics simulations confirm our theoretical predictions and show that they also hold beyond the validity range of our analytical approach, pointing to a universal behavior.
authors.affiliation: Gulliver, CNRS, ESPCI Paris, PSL Research University, 10 rue Vauquelin, 75005 Paris, France.|Département de Physique, ENS, PSL Research University, 24 Rue Lhomond, 75005 Paris, France.
authors.forename: Alexis
authors.initials: A
authors.lastname: Poncet
authors.affiliation: Laboratoire de Physique Théorique de la Matière Condensée, CNRS/UPMC, 4 Place Jussieu, F-75005 Paris, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Bénichou
authors.affiliation: Gulliver, CNRS, ESPCI Paris, PSL Research University, 10 rue Vauquelin, 75005 Paris, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Démery
authors.affiliation: Laboratoire de Physique Théorique de la Matière Condensée, CNRS/UPMC, 4 Place Jussieu, F-75005 Paris, France.
authors.forename: Gleb
authors.initials: G
authors.lastname: Oshanin