arXiv physics/04040122004-04physics.atom-ph

Deeply subrecoil two-dimensional Raman cooling

V. Boyer, L. J. Lising, S. L. Rolston, W. D. Phillips

备注：: 8 pages, 6 figures, submitted to Phys. Rev. A
DOI：: 10.1103/PhysRevA.70.043405

英文摘要：

We report the implementation of a two-dimensional Raman cooling scheme using sequential excitations along the orthogonal axes. Using square pulses, we have cooled a cloud of ultracold Cesium atoms down to an RMS velocity spread of 0.39(5) recoil velocity, corresponding to an effective temperature of 30 nK (0.15 T_rec). This technique can be useful to improve cold atom atomic clocks, and is particularly relevant for clocks in microgravity.

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