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Electronic coherence in $delta$-Pu: A DMFT study

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 نشر من قبل Chris Marianetti
 تاريخ النشر 2008
  مجال البحث فيزياء
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A combination of Density Functional Theory and the Dynamical Mean Field theory (DMFT) is used to calculate the magnetic susceptibility, heat capacity, and the temperature dependence of the valence band photoemission spectra. The continuous-time hybridization expansion quantum Monte-Carlo is utilized to provide the first approximation-free DMFT solution of emph{fcc} $delta$-Pu which includes the full rotationally-invariant exchange interaction. We predict that $delta$-Pu has a Pauli-like magnetic susceptibility near ambient temperature, as in experiment, indicating that electronic coherence causes the absence of local moments. Additionally, We show that volume expansion causes a crossover from incoherent to coherent electronic behavior at increasingly lower temperatures.



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