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Using surface-wave spectroscopy to characterize tilt modes of a vortex in a Bose-Einstein Condensate

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 Added by Paul C. Haljan
 Publication date 2000
  fields Physics
and research's language is English




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A vortex in a condensate in a nonspherical trapping potential will in general experience a torque. The torque will induce tilting of the direction of the vortex axis. We observe this behavior experimentally and show that by applying small distortions to the trapping potential, we can control the tilting behaviour. By suppressing vortex tilt, we have been able to hold the vortex axis along the line of sight for up to 15 seconds. Alternatively, we can induce a 180 degree tilt, effectively reversing the charge on the vortex as observed in the lab frame. We characterize the vortex non-destructively with a surface-wave spectroscopic technique.



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