γ-Mn at the border between weak and strong correlations |
| |
Authors: | I Di Marco J Minár J Braun M I Katsnelson A Grechnev H Ebert A I Lichtenstein and O Eriksson |
| |
Institution: | Laboratorio de Novos Materiais Semicondutores, Instituto de Fisica, Universidade de Sao Paulo, Rua do Matao, travessa R, 187, 05508-900 Butanta, Sao Paulo, SP, Brasil |
| |
Abstract: | We investigate the role of magnetic fluctuations in the spectral properties of paramagnetic γ-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 γ-Mn is very sensitive
to the value of Hund’s exchange parameter. Comparison with the experimental photoemission spectra demonstrates that γ-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. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|