September 9, 2016
Universal dynamics of bosons across a quantum phase transition
A Bose-Einstein condensate when shaken appropriately shows universal dynamics at a ferromagnetic quantum critical point. By ramping the modulation strength, the emergence and growth of the pseudo-spin fluctuations are universal in the normalized coordinate (bottom graphic, squares), and are in good agreement with theoretical calculations (bottom graph, line).
We expect this result is generalizable to a large class of quantum critical dynamics in the same universality class.
"Universal space-time scaling symmetry in the dynamics of bosons across a quantum phase transition," Logan W. Clark, Lei Feng and Cheng Chin, Science 354 (6312), 606-610. DOI: 10.1126/science.aaf9657