Dark-soliton dynamics in Bose-Einstein condensates at finite temperature

We find two types of moving dark soliton textures in elongated condensates: nonstationary kinks and proper dark solitons. The latter have a flat notch region and we obtain the diagram of their dynamical stability. At finite temperatures the dynamically stable solitons decay due to the thermodynamic instability. We develop a theory of their dissipative dynamics and explain experimental data.

arXiv:cond-mat/0111506Physical Review LettersAug 21, 2002257 citations

Dark-soliton dynamics in Bose-Einstein condensates at finite temperature

B. Jackson, Nick P. Proukakis, Carlo Barenghi

Published Dec 31, 2007• 0 citations

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DOI: 10.25405/ncl.34634592

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Dark-soliton dynamics in Bose-Einstein condensates at finite temperature

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{k}_{B}T

, we find average soliton lifetimes to scale with temperature as $\ensuremath{\tau}\ensuremath{\sim}{T}^{\ensuremath{-}4}$, in agreement with predictions previously made for the low-temperature regime ${k}_{B}T\ensuremath{\ll}\ensuremath{\mu}$. The model is also shown to capture the experimentally relevant decrease in the visibility of an oscillating soliton due to the presence of background fluctuations.