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Multi-Orbital Hubbard Model in Infinite Dimensions: Quantum Monte Carlo Calculation

J. E. Han·M. Jarrell·D. L. Cox
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Abstract

Using Quantum Monte Carlo we compute thermodynamics and spectra for the orbitally degenerate Hubbard model in infinite spatial dimensions. With increasing orbital degeneracy we find in the one-particle spectra: broader Hubbard bands (consistent with increased kinetic energy), a narrowing Mott gap, and increasing quasi-particle spectral weight. In opposition, Hund's rule exchange coupling decreases the critical on-site Coulomb energy for the Mott transition. The metallic regime resistivity for two-fold degeneracy is quadratic-in-temperature at low temperatures.

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J. E. Han, M. Jarrell, D. L. Cox. 1998-06-15. Multi-Orbital Hubbard Model in Infinite Dimensions: Quantum Monte Carlo Calculation. https://doi.org/10.1103/physrevb.58.r4199

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