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Quasiparticle dynamics in a Bose insulator probed by inter-band Bragg spectroscopy

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 نشر من قبل Nicole Fabbri
 تاريخ النشر 2011
  مجال البحث فيزياء
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We investigate experimentally and theoretically the dynamical properties of a Mott insulator in decoupled one-dimensional chains. Using a theoretical analysis of the Bragg excitation scheme we show that the spectrum of inter-band transitions holds information on the single-particle Greens function of the insulator. In particular the existence of particle-hole coherence due to quantum fluctuations in the Mott state is clearly seen in the Bragg spectra and quantified. Finally we propose a scheme to directly measure the full, momentum resolved spectral function as obtained in angle-resolved photoemission spectroscopy of solids.

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