arXiv:1509.02173 · Physical Review Letters

Observation of Scaling in the Dynamics of a Strongly Quenched Quantum Gas

E. Nicklas, M. Karl, M. Höfer, Aisling Johnson, Wolfgang Muessel, Helmut Strobel, Jiří Tomkovič, Thomas Gasenzer, Markus K. Oberthaler

Published Dec 11, 2015• 117 citations

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Abstract

We report on the experimental observation of scaling in the time evolution following a sudden quench into the vicinity of a quantum critical point. The experimental system, a two-component Bose gas with coherent exchange between the constituents, allows for the necessary high level of control of parameters as well as the access to time-resolved spatial correlation functions. The theoretical analysis reveals that when quenching the system close to the critical point, the energy introduced by the quench leads to a short-time evolution exhibiting crossover reminiscent of the finite-temperature critical properties in the system's universality class. Observing the time evolution after a quench represents a paradigm shift in accessing and probing experimentally universal properties close to a quantum critical point and allows in a new way benchmarking of quantum many-body theory with experiments.

DOI: 10.1103/physrevlett.115.245301

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