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Ground state cooling of atoms in optical lattices

M. Popp·J. J. Garcia-Ripoll·K. G. H. Vollbrecht·J. I. Cirac
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Abstract

We propose two schemes for cooling bosonic and fermionic atoms that are trapped in a deep optical lattice. The first scheme is a quantum algorithm based on particle number filtering and state dependent lattice shifts. The second protocol alternates filtering with a redistribution of particles by means of quantum tunnelling. We provide a complete theoretical analysis of both schemes and characterize the cooling efficiency in terms of the entropy. Our schemes do not require addressing of single lattice sites and use a novel method, which is based on coherent laser control, to perform very fast filtering.

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M. Popp, J. J. Garcia-Ripoll, K. G. H. Vollbrecht, J. I. Cirac. 2006-07-28. Ground state cooling of atoms in optical lattices. https://doi.org/10.1103/physreva.74.013622

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