Gamma-Mn at the border between weak and strong correlations
| Autor: | J. Minár, Mikhail I. Katsnelson, Alexei Grechnev, Jürgen Braun, I. Di Marco, Hubert Ebert, Olle Eriksson, Alexander I. Lichtenstein |
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| Rok vydání: | 2009 |
| Předmět: |
Physics
Condensed matter physics Magnetic moment Strongly Correlated Electrons (cond-mat.str-el) Theory of Condensed Matter Minor (linear algebra) FOS: Physical sciences Solver Condensed Matter Physics Spectral line Electronic Optical and Magnetic Materials Condensed Matter - Other Condensed Matter Paramagnetism Condensed Matter - Strongly Correlated Electrons Condensed Matter::Strongly Correlated Electrons Local-density approximation Quantum Hubbard band Other Condensed Matter (cond-mat.other) |
| Zdroj: | European Physical Journal B, 72, 4, pp. 473-478 European Physical Journal B, 72, 473-478 |
| ISSN: | 1434-6028 |
| DOI: | 10.1140/epjb/e2009-00390-1 |
| Popis: | We investigate the role of magnetic fluctuations in the spectral properties of paramagnetic gamma-Mn. Two methods are employed. The Local Density Approximation plus Dynamical Mean-Field Theory together with the numerically exact quantum Monte-Carlo solver is used as a reference for the spectral properties. Then the same scheme is used with the computationally less demanding perturbative spin-polarized fluctuation-exchange solver in combination with the Disordered Local Moment approach, and photoemission spectra are calculated within the one-step model. It is shown that the formation of local magnetic moments in gamma-Mn is very sensitive to the value of Hund's exchange parameter. Comparison with the experimental photoemission spectra demonstrates that gamma-Mn is a strongly correlated system, with the Hubbard band formation, which cannot be described by the perturbative approach. However, minor change of parameters would transform it into a weakly correlated system. 6 pages, 4 figures |
| Databáze: | OpenAIRE |
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