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Quantum Monte Carlo Study of an Extended Hubbard Model on a Two-leg Ladder

Tomo Munehisa·Yasuko Munehisa
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Abstract

An extended Hubbard model on a two-leg ladder is numerically studied by means of the quantum Monte Carlo techniques. The model we study has the nearest-neighbor interactions which are repulsive along chains and attractive for rungs. The plots of the doping parameter versus the chemical potential show two cliff-like regions and a large plateau region. Results on the charge susceptibility suggest it diverges in these cliff-like regions. These observations might imply a signal to the phase separation, which should be related to the effective attractive interactions along chains.

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Tomo Munehisa, Yasuko Munehisa. 1997-09-16. Quantum Monte Carlo Study of an Extended Hubbard Model on a Two-leg Ladder. https://doi.org/10.1143/jpsj.66.3876

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