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arXiv · 1308.3125

Subrecoil cavity cooling towards degeneracy: A numerical study

Raimar M. Sandner·Wolfgang Niedenzu·Helmut Ritsch
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Abstract

We present a detailed numerical analysis of the temperature limit and timescale of cavity cooling of a dilute gas in the quantum regime for particles and light. For a cavity with a linewidth smaller than the recoil frequency efficient cooling towards quantum degeneracy is facilitated by applying a tailored sequence of laser pulses transferring the particles towards lower momenta. Two-particle Monte Carlo wave function simulations reveal strongly improved cooling properties for a ring versus a standing-wave geometry. Distinct quantum correlations and cooling limits for bosons and fermions demonstrate quantum statistical effects. In particular, in ring cavities the photon-mediated long-range interaction favours momentum-space pairing of bosons, while fermion pairs exhibit anti-correlated or uncorrelated momenta. The results are consistent with recent experiments and give encouraging prospects to achieve sufficient conditions for the condensation of a wide class of polarisable particles via cavity cooling.

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Raimar M. Sandner, Wolfgang Niedenzu, Helmut Ritsch. 2013-12-10. Subrecoil cavity cooling towards degeneracy: A numerical study. https://doi.org/10.1209/0295-5075%2F104%2F43001

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