Observation of two non-thermal fixed points for the same microscopic symmetry

Abstract:

Close to equilibrium, the underlying symmetries of a system determine its possible universal behavior. Far from equilibrium, however, different universal phenomena associated with the existence of multiple non-thermal fixed points can be realized for given microscopic symmetries. Here, we study this phenomenon using a quasi-one-dimensional spinor Bose-Einstein condensate. We prepare two different initial conditions and observe two distinct universal scaling dynamics with different exponents. Measurements of the complex-valued order parameter with spatial resolution allow us to characterize the phase-amplitude excitations for the two scenarios. Our study provides new insights into the phenomenon of universal dynamics far from equilibrium and opens a path towards mapping out the associated basins of non-thermal fixed points.

S. Lannig, M. Prüfer, Y. Deller, I. Siovitz, J. Dreher, T. Gasenzer, H. Strobel, M. K. Oberthaler,
„Observation of two non-thermal fixed points for the same microscopic symmetry“, 28. Juni
2023, arXiv:2306.16497 (2023).

https://arxiv.org/abs/2306.16497

Related to Project A04