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arXiv · 1307.6004

Time-of-Flight Roton Spectroscopy in Dipolar Bose-Einstein Condensates

M. Jona-Lasinio·K. Łakomy·L. Santos
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Abstract

Dipolar Bose-Einstein condensates may present a rotonlike dispersion minimum, which has yet to be observed in experiments. We discuss a simple method to reveal roton excitations, based on the response of quasi-two-dimensional dipolar condensates against a weak lattice potential. By employing numerical simulations for realistic scenarios, we analyze the response of the system as a function of both the lattice spacing and the s-wave scattering length, showing that the roton minimum may be readily revealed in current experiments by the resonant population of Bragg peaks in time-of-flight measurements.

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M. Jona-Lasinio, K. Łakomy, L. Santos. 2013-09-03. Time-of-Flight Roton Spectroscopy in Dipolar Bose-Einstein Condensates. https://doi.org/10.1103/physreva.88.025603

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