Alternate-current dynamic reorganization and nonequilibrium phase transition in driven vortex matter

Abstract

Externally driven glassy systems may undergo nonequilibrium phase (NEPTs). In particular, ac-driven systems display special features, such as those observed in the vortex matter of NbSe2, where oscillatory drives reorganize the system into partially ordered vortex lattices. We provide experimental evidence for this dynamic reorganization and we show an unambiguous signature of its connection with an NEPT driven by ac forces. We perform a scaling analysis and we estimate critical exponents for this transition. Our results share similarities with some glass-to-viscous-liquid NEPTs and invite a search for similar physics in other elastic disordered media.