gamma-Mn at the border between weak and strong correlations
2009 (English)In: European Physical Journal B: Condensed Matter Physics, ISSN 1434-6028, E-ISSN 1434-6036, Vol. 72, no 4, 473-478 p.Article in journal (Refereed) Published
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.
Place, publisher, year, edition, pages
2009. Vol. 72, no 4, 473-478 p.
IdentifiersURN: urn:nbn:se:uu:diva-127372DOI: 10.1140/epjb/e2009-00390-1ISI: 000272803300001OAI: oai:DiVA.org:uu-127372DiVA: diva2:329718