Bath-mediated interactions between driven tracers in dense single files

Abstract

Single-file transport, where particles cannot bypass each other, has been observed in various experimental setups. In such systems, the behavior of a tracer particle (TP) is subdiffusive, which originates from strong correlations between particles. These correlations are especially marked when the TP is driven and leads to inhomogeneous density profiles. Determining the impact of this inhomogeneity when several TPs are driven in the system is a key question, related to the general issue of bath-mediated interactions, which are known to induce collective motion and lead to the formation of clusters or lanes in a variety of systems. Quantifying this collective behavior, the emerging interactions, and their dependence on the amplitude of forces driving the TPs remains a challenging but largely unresolved issue. Here, considering dense single-file systems, we analytically determine the entire dynamics of the correlations and reveal out-of-equilibrium cooperativity and competition effects between driven TPs.