Random dispersion approximation for the Hubbard model
نویسندگان
چکیده
منابع مشابه
Random Dispersion Approximation for the Hubbard model
We use the Random Dispersion Approximation (RDA) to study the Mott-Hubbard transition in the Hubbard model at half band filling. The RDA becomes exact for the Hubbard model in infinite dimensions. We implement the RDA on finite chains and employ the Lanczos exact diagonalization method in real space to calculate the ground-state energy, the average double occupancy, the charge gap, the momentum...
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It is shown that the low-energy single-particle excitation-spectrum of the three-band Hubbard model at hole-dopings away from half-filling agrees remarkably well with Quantum Monte Carlo data and spectroscopic experiments within the framework of a conserving approximation that includes selfconsistently the interaction with charge, spin, and two-particle fluctuations. The dispersion of the quasi...
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ژورنال
عنوان ژورنال: The European Physical Journal B
سال: 2008
ISSN: 1434-6028,1434-6036
DOI: 10.1140/epjb/e2008-00402-8