Spontaneous non-equilibrium magnetism via Berryogenesis in driven electronic systems

Spontaneous symmetry breaking is central to the description of interacting phases of matter. In this talk I will discuss a novel type of collective mode symmetry breaking transition in which a driven interacting system subject to a time-reversal symmetric driving field can spontaneously magnetize. Strong internal ac fields of a metal driven close to its plasmon resonance may enable Berryogenesis: the spontaneous generation of a self-induced Bloch band Berry flux. The self-induced Berry flux supports and is sustained by a circulating plasmonic motion, which may arise even for a linearly polarized driving field. Berryogenesis relies on feedback due to interband coherences induced by internal fields, and may readily occur in a wide variety of multiband systems. We anticipate that graphene devices, in particular, provide a natural platform to achieve Berryogenesis and plasmon-mediated spontaneous non-equilibrium magnetism with present-day capabilities.