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Spin-charge separation in cold Fermi-gases: a real time analysis

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 نشر من قبل Corinna Kollath
 تاريخ النشر 2005
  مجال البحث فيزياء
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Using the adaptive time-dependent density-matrix renormalization group method for the 1D Hubbard model, the splitting of local perturbations into separate wave packets carrying charge and spin is observed in real-time. We show the robustness of this separation beyond the low-energy Luttinger liquid theory by studying the time-evolution of single particle excitations and density wave packets. A striking signature of spin-charge separation is found in 1D cold Fermi gases in a harmonic trap at the boundary between liquid and Mott-insulating phases. We give quantitative estimates for an experimental observation of spin-charge separation in an array of atomic wires.



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