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Exact Diagonalization Approach for the infinite D Hubbard Model

Michel Caffarel·Werner Krauth
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Abstract

We present a powerful method for calculating the thermodynamic properties of the Hubbard model in infinite dimensions, using an exact diagonalization of an Anderson model with a finite number of sites. At finite temperatures, the explicit diagonalization of the Anderson Hamiltonian allows the calculation of Green's functions with a resolution far superior to that of Quantum Monte Carlo calculations. At zero temperature, the Lanczòs method is used and yields the essentially exact zero-temperature solution of the model, except in a region of very small frequencies. Numerical results for the half-filled case in the paramagnetic phase (quasi-particle weight, self-energy, and also real-frequency spectral densities) are presented.

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Michel Caffarel, Werner Krauth. 1993-06-28. Exact Diagonalization Approach for the infinite D Hubbard Model. https://arxiv.org/abs/cond-mat/9306057

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