Condensed Matter Theory Seminar | September 04, 10:00

Driven-dissipative coupled Ising models: a new non-equilibrium universality class


Driven-dissipative systems can potentially exhibit non-equilibrium phenomena that are absent in their equilibrium counterparts. However, phase transitions present in these systems generically exhibit an effectively classical, equilibrium behavior in spite of their non-equilibrium origin. In this talk, I investigate an experimentally motivated model where two Ising-like order parameters interact and form a multicritical point. I will discuss how at such a multicritical point, new non-equilibrium criticality can emerge. These non-equilibrium multicritical points exhibit a variety of exotic phenomena with no counterpart in equilibrium, including spiraling phase boundaries, the emergence of discrete scale invariance rather than the more familiar continuous scale invariance, and the violation of the fluctuation-dissipation theorem at all length scales, resulting in a sytem which becomes “hotter” and “hotter” at longer and longer wavelengths. Furthermore, I will discuss how for more complex order parameters with a different form of symmetry, additional non-equilibrium multicritical points can emerge.


Jeremy Young, University of Maryland
Seminar Room 0.03, ETP
Contact: Sebastian Diehl