2009/12/31 by Ryan Wilson, Ryan M. Wilson, Shai Ronen +1 · 1 citation
Physics and Astronomy · #Bose–Einstein condensate #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Critical ionization velocity #Dipole #Mechanics #Physics #Quantum mechanics #Quantum, superfluid, helium dynamics #Quasiparticle #Roton #Strong Light-Matter Interactions #Superconductivity #Superfluid helium-4 #Superfluidity #Vortex #cond-mat.quant-gas
paper · pdf · doi:10.1103/physrevlett.104.094501
5 pages, 4 figures, version accepted to PRL
arxiv created 2010/02/08 · openalex publication_date 2010/03/01 · arxiv updated 2015/05/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate the superfluid properties of a dipolar Bose-Einstein condensate (BEC) in a fully three-dimensional trap. Specifically, we estimate a superfluid critical velocity for this system by applying the Landau criterion to its discrete quasiparticle spectrum. We test this critical velocity by direct numerical simulation of condensate depletion as a blue-detuned laser moves through the condensate. In both cases, the presence of the roton in the spectrum serves to lower the critical velocity beyond a critical particle number. Since the shape of the dispersion, and hence the roton minimum, is tunable as a function of particle number, we thereby propose an experiment that can simultaneously measure the Landau critical velocity of a dipolar BEC and demonstrate the presence of the roton in this system.