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Effective lattice actions for correlated electrons

Antimo Angelucci
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Abstract

We present an exact, unconstrained representation of the electron operators in terms of operators of opposite statistics. We propose a path--integral representation for the $t$-$J$ model and introduce a parameter controlling the semiclassical behaviour. We extend the functional approach to the Hubbard model and show that the mean--field theory is equivalent to considering, at Hamiltonian level, the Falikov--Kimball model. Connections with a bond-charge model are also discussed.

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Antimo Angelucci. 1994-12-20. Effective lattice actions for correlated electrons. https://doi.org/10.1103/physrevb.51.11580

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