Dr. Cheng Chin

James Franck Institute, Enrico Fermi Institute and Department of Physics

University of Chicago

From Cosmology to Cold Atoms: Observation of Sakharov Acoustic Oscillations in Quenched Atomic Superfluids

102 Cardwell Hall

November 18, 2013

4:30 p.m.

Sakharov oscillation, conventionally discussed in the context of early universe evolution and the anisotropy of cosmic microwave background radiation, is the manifestation of interfering acoustic waves generated in an ideal fluid. We report a laboratory simulation of Sakharov oscillations in an atomic superfluid. We quench the interactions between atoms and monitor the subsequent density fluctuations at different time and length scales. Sakharov oscillations are identified as the multi-peak structure in the density power spectrum, resembling that of the anisotropy of cosmic microwave background radiation. From the Sakharov oscillations, we determine the sonic horizon, providing new perspectives to extend quantum simulation to other intriguing cosmological and gravitational phenomena.