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تسجيل مستخدم جديدCharge self-consistency in density functional theory + dynamical mean field theory: k-space reoccupation and orbital order
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We study effects of charge self-consistency within the combination of density functional theory (DFT; Wien2k) with dynamical mean field theory (DMFT; w2dynamics) in a basis of maximally localized Wannier orbitals. Using the example of two cuprates, we demonstrate that even if there is only a single Wannier orbital with fixed filling, a noteworthy charge redistribution can occur. This effect stems from a reoccupation of the Wannier orbital in k-space when going from the single, metallic DFT band to the split, insulating Hubbard bands of DMFT. We analyze another charge self-consistency effect beyond moving charge from one site to another: the correlation-enhanced orbital polarization in a freestanding layer of SrVO3.
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We propose a hybrid approach which employs the dynamical mean-field theory (DMFT) self-energy for the correlated, typically rather localized orbitals and a conventional density functional theory (DFT) exchange-correlation potential for the less corre
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