From hindrance to catalyst: Potential roughness accelerates escape far from equilibrium

Abstract

Activated escape from metastable states is a foundational concept in rate theory, underpinning diverse phenomena from chemical reactions to protein folding. A long-standing paradigm posits that potential energy landscape roughness invariably impedes kinetics by creating a multitude of local traps that suppress escape rates. Challenging this established paradigm, we investigate particles driven by discrete, non-equilibrium shot noise and reveal a striking inversion of this role. We demonstrate that, contrary to expectation, roughness can transform from a kinetic impediment into a potent catalyst, dramatically accelerating escape. The escape rate exhibits a striking non-monotonic dependence on the roughness amplitude, peaking at an optimal value. We attribute this counter-intuitive effect to a non-equilibrium mechanism we term slide inhibition, where local minima act as transient anchors. These anchors arrest dissipative relaxation between stochastic kicks, enabling a cumulative, ratchet-like ascent over the main energy barrier. The intrinsically non-equilibrium character of this synergy is powerfully underscored by the finding that thermal noise becomes destructive, destabilizing these crucial footholds. Our work unveils a constructive synergy between spatial disorder and non-equilibrium fluctuations, fundamentally recasting landscape roughness from a passive obstacle into a functional element for manipulating activated transport far from equilibrium.