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Momentum-resolved spectral functions of SrVO$_3$ calculated by LDA+DMFT

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 نشر من قبل Karsten Held
 تاريخ النشر 2005
  مجال البحث فيزياء
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LDA+DMFT, the merger of density functional theory in the local density approximation and dynamical mean-field theory, has been mostly employed to calculate k-integrated spectra accessible by photoemission spectroscopy. In this paper, we calculate k-resolved spectral functions by LDA+DMFT. To this end, we employ the Nth order muffin-tin (NMTO) downfolding to set up an effective low-energy Hamiltonian with three t_2g orbitals. This downfolded Hamiltonian is solved by DMFT yielding k-dependent spectra. Our results show renormalized quasiparticle bands over a broad energy range from -0.7 eV to +0.9 eV with small ``kinks, discernible in the dispersion below the Fermi energy.


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