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Accurate numerical solution to the finite-size Dicke model

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 نشر من قبل Qing-Hu Chen
 تاريخ النشر 2008
  مجال البحث فيزياء
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By using extended bosonic coherent states, a new technique to solve the Dicke model exactly is proposed in the numerical sense. The accessible system size is two orders of magnitude higher than that reported in literature. Finite-size scaling for several observables, such as the ground-state energy, Berry phase, and concurrence are analyzed. The existing discrepancy for the scaling exponent of the concurrence is reconciled.



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