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Discerning Incompressible and Compressible Phases of Cold Atoms in Optical Lattices

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 نشر من قبل Vito W. Scarola
 تاريخ النشر 2009
  مجال البحث فيزياء
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Experiments with cold atoms trapped in optical lattices offer the potential to realize a variety of novel phases but suffer from severe spatial inhomogeneity that can obscure signatures of new phases of matter and phase boundaries. We use a high temperature series expansion to show that compressibility in the core of a trapped Fermi-Hubbard system is related to measurements of changes in double occupancy. This core compressibility filters out edge effects, offering a direct probe of compressibility independent of inhomogeneity. A comparison with experiments is made.



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