2015/09/30 by Geol Moon, Woo Jin Kwon, Hyunjik Lee +1 · 2 citations
Physics and Astronomy · #Bose–Einstein condensate #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Dimensionless quantity #Dissipative system #Mechanics #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Quantum, superfluid, helium dynamics #Vortex #Vortex state #cond-mat.quant-gas
paper · pdf · doi:10.1103/physreva.92.051601
published as Physical Review A 92, 051601(R) (2015) · 5 pages, 4 figures
openalex publication_date 2015/11/20 · arxiv created 2015/11/26 · arxiv updated 2015/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate the dissipative dynamics of a corotating vortex pair in a highly oblate axisymmetric Bose-Einstein condensate trapped in a harmonic potential. The initial vortex state is prepared by creating a doubly charged vortex at the center of the condensate and letting it dissociate into two singly charged vortices. The separation of the vortex pair gradually increases over time and its increasing rate becomes higher with increasing the sample temperature T. The evolution of the vortex state is well described with a dissipative point vortex model including longitudinal friction on the vortex motion. For condensates of sodium atoms having a chemical potential of \ensuremathμ\ensuremath≈kB\ifmmode×\else\texttimes\fi120 nK, we find that the dimensionless friction coefficient \ensuremathα increases from 0.01 to 0.03 over the temperature range of 200nK<T<450 nK.