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Collective Sideband Cooling in an Optical Ring Cavity

Th. Elsaesser·B. Nagorny·A. Hemmerich
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Abstract

We propose a cavity based laser cooling and trapping scheme, providing tight confinement and cooling to very low temperatures, without degradation at high particle densities. A bidirectionally pumped ring cavity builds up a resonantly enhanced optical standing wave which acts to confine polarizable particles in deep potential wells. The particle localization yields a coupling of the degenerate travelling wave modes via coherent photon redistribution. This induces a splitting of the cavity resonances with a high frequency component, that is tuned to the anti-Stokes Raman sideband of the particles oscillating in the potential wells, yielding cooling due to excess anti-Stokes scattering. Tight confinement in the optical lattice together with the prediction, that more than 50% of the trapped particles can be cooled into the motional ground state, promise high phase space densities.

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Th. Elsaesser, B. Nagorny, A. Hemmerich. 2003-02-18. Collective Sideband Cooling in an Optical Ring Cavity. https://doi.org/10.1103/physreva.67.051401

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