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Static vs. dynamical mean field theory of Mott antiferromagnets

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

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.

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G. Sangiovanni, A. Toschi, E. Koch, K. Held, M. Capone, C. Castellani, O. Gunnarsson, S. -K. Mo, J. W. Allen, H. -D. Kim, A. Sekiyama, A. Yamasaki, S. Suga, P. Metcalf. 2006-06-04. Static vs. dynamical mean field theory of Mott antiferromagnets. https://doi.org/10.1103/physrevb.73.205121

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