Observation of a dynamical topological phase transition

22 August 2016

Photo: AG Sengstock

We have achieved the first experimental observation of a dynamical phase transition - a recently introduced concept for the description of the dynamics of a many-body quantum state far from equilibrium, where order appears and disappears as a function of time rather than temperature. We perform time and momentum-resolved state tomography of our fermionic many-body state after a quench within the Haldane model, realized by lattice shaking, and observe the appearance of dynamical vortices in the phase profile. This dynamical order is sensitive to the change of Chern number across the quench and therefore allows mapping out the Haldane-like Floquet phase diagram, which demonstrates a new approach to the study of phase diagrams.

arxiv:1608.05616

Nature Physics 14, 265 (2018)

Press coverage: UHH, CUI

Siehe auch den Brennpunkt "Quantenphasen, aber dynamisch" von Patrick Windpassinger und Ferdinand Schmidt-Kaler.

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