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Isosbestic points in the spectral function of correlated electrons

M. Eckstein·M. Kollar·D. Vollhardt
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Abstract

We investigate the properties of the spectral function A(omega,U) of correlated electrons within the Hubbard model and dynamical mean-field theory. Curves of A(omega,U) vs. omega for different values of the interaction U are found to intersect near the band-edges of the non-interacting system. For a wide range of U the crossing points are located within a sharply confined region. The precise location of these 'isosbestic points' depends on details of the non-interacting band structure. Isosbestic points of dynamic quantities therefore provide valuable insights into microscopic energy scales of correlated systems.

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M. Eckstein, M. Kollar, D. Vollhardt. 2006-09-19. Isosbestic points in the spectral function of correlated electrons. https://doi.org/10.1007/s10909-007-9311-3

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