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arXiv · 0807.0726

Critical velocities in two-component superfluid Bose gases

L. Yu. Kravchenko·D. V. Fil
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Abstract

On the ground of the Landau criterion we study the behavior of critical velocities in a superfluid two-component Bose gas. It is found that under motion of the components with different velocities the velocity of each component should not be lower than a minimum phase velocity of elementary excitations (s_). The Landau criterion yields a relation between the critical velocities of the components (v_{c1}, v_{c2}). The velocity of one or even both components may exceed s_. The maximum value of the critical velocity of a given component can be reached when the other component does not move. The approach is generalized for a two-component condensate confined in a cylindrical harmonic potential. PACS numbers: 03.75.Kk,03.75.Mn

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L. Yu. Kravchenko, D. V. Fil. 2008-07-04. Critical velocities in two-component superfluid Bose gases. https://doi.org/10.1007/s10909-007-9595-3

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