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Critical Velocity of Vortex Nucleation in Rotating Superfluid 3He-A

V. M. H. Ruutu·J. Kopu·M. Krusius·Ü. Parts·B. Placais·E. V. Thuneberg·W. Xu
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Abstract

We have measured the critical velocity v_c at which 3He-A in a rotating cylinder becomes unstable against the formation of quantized vortex lines with continuous (singularity-free) core structure. We find that v_c is distributed between a maximum and minimum limit, which we ascribe to a dependence on the texture of the orbital angular momentum l(r) in the cylinder. Slow cool down through T_c in rotation yields l(r) textures for which the measured v_c's are in good agreement with the calculated instability of the expected l texture.

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V. M. H. Ruutu, J. Kopu, M. Krusius, Ü. Parts, B. Placais, E. V. Thuneberg, W. Xu. 1997-08-29. Critical Velocity of Vortex Nucleation in Rotating Superfluid 3He-A. https://doi.org/10.1103/physrevlett.79.5058

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