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Calculation of photoemission spectra of the doped Mott insulator La_{1-x}Sr_xTiO_3 using LDA+DMFT(QMC)

I. A. Nekrasov·K. Held·N. Blümer·A. I. Poteryaev·V. I. Anisimov·D. Vollhardt
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Abstract

The spectral properties of La$_{1-x}$Sr$_{x}$TiO$_{3}$, a doped Mott insulator with strong Coulomb correlations, are calculated with the ab initio computational scheme LDA+DMFT(QMC). It starts from the non-interacting electronic band structure as calculated by the local density approximation (LDA), and introduces the missing correlations by the dynamical mean-field theory (DMFT), using numerically exact quantum Monte-Carlo (QMC) techniques to solve the resulting self-consistent multi-band single-impurity problem. The results of the LDA+DMFT(QMC) approach for the photoemission spectra of La$_{1-x}$Sr$_{x}$TiO$_{3}$ are in good agreement with experiment and represent a considerable qualitative and quantitative improvement on standard LDA calculations.

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I. A. Nekrasov, K. Held, N. Blümer, A. I. Poteryaev, V. I. Anisimov, D. Vollhardt. 2000-07-27. Calculation of photoemission spectra of the doped Mott insulator La_{1-x}Sr_xTiO_3 using LDA+DMFT(QMC). https://doi.org/10.1007/s100510070077

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