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Experimental studies of equilibrium vortex properties in a Bose-condensed gas

I. Coddington·P. C. Haljan·P. Engels·V. Schweikhard·S. Tung·E. A. Cornell
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Abstract

We characterize several equilibrium vortex effects in a rotating Bose-Einstein condensate. Specifically we attempt precision measurements of vortex lattice spacing and the vortex core size over a range of condensate densities and rotation rates. These measurements are supplemented by numerical simulations, and both experimental and numerical data are compared to theory predictions of Sheehy and Radzihovsky [17] (cond-mat/0402637) and Baym and Pethick [25] (cond-mat/0308325). Finally, we study the effect of the centrifugal weakening of the trapping spring constants on the critical temperature for quantum degeneracy and the effects of finite temperature on vortex contrast.

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I. Coddington, P. C. Haljan, P. Engels, V. Schweikhard, S. Tung, E. A. Cornell. 2004-10-05. Experimental studies of equilibrium vortex properties in a Bose-condensed gas. https://doi.org/10.1103/physreva.70.063607

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