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arXiv · 1401.0735

Dynamics of correlations in a quasi-2D dipolar Bose gas following a quantum quench

Abstract

We study the evolution of correlations in a quasi-2D dipolar gas driven out-of-equilibrium by a sudden ramp of the interaction strength. For sufficiently strong ramps, the momentum distribution, excited fraction and density-density correlation function all display pronounced features that are directly related to the appearance of a roton minimum in the underlying spectrum. Our study suggests that the evolution of correlations following a quench can be used as a probe of roton-like excitations in a dipolar gas. We also find that the build up of density-density correlations following a quench occurs much more slowly in the dipolar gas compared to a non-dipolar gas, owing to the long-range interactions.

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Stefan S. Natu, L. Campanello, S. Das Sarma. 2014-10-17. Dynamics of correlations in a quasi-2D dipolar Bose gas following a quantum quench. https://doi.org/10.1103/physreva.90.043617

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