Static vs. dynamical mean field theory of Mott antiferromagnets

Sangiovanni, G.; Toschi, A.; Koch, E.; Held, K.; Capone, M.; Castellani, C.; Gunnarsson, O.; Mo, S. -K.; Allen, J. W.; Kim, H. -D.; Sekiyama, A.; Yamasaki, A.; Suga, S.; Metcalf, P.

Static vs. dynamical mean field theory of Mott antiferromagnets

Authors

Description

Studying the antiferromagnetic phase of the Hubbard model by dynamical mean field theory, we observe striking differences with static (Hartree-Fock) mean field: The Slater band is strongly renormalized and spectral weight is transferred to spin-polaron side bands. Already for intermediate values of the interaction $U$ the overall bandwidth is larger than in Hartree-Fock, and the gap is considerably smaller. Such differences survive any renormalization of $U$. Our photoemission experiments for Cr-doped V$_2$O$_3$ show spectra qualitatively well described by dynamical mean field theory.
6 pages, 5 figures - one figure added and further details about quasiparticle dispersion