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Quantum Monte Carlo simulations of infinitely strongly correlated fermions

Michael Brunner·Alejandro Muramatsu
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Abstract

Numerical simulations of the two-dimensional t-J model in the limit $J/t \ll 1$ are performed for rather large systems (up to $N = 12 \times 12$) using a world-line loop-algorithm. It is shown that in the one-hole case with J=0, where no minus signs appear, very low temperatures ($βt \sim 3000$) are necessary in order to reach Nagaoka's state. $J/t \ltsim 0.05$ leads to the formation of partially polarized systems, whereas $J/t \gtsim 0.05 $ corresponds to minimal spin. The two-hole case shows enhanced total spin up to the lowest attainable temperatures ($βt = 150$).

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Michael Brunner, Alejandro Muramatsu. 1997-07-10. Quantum Monte Carlo simulations of infinitely strongly correlated fermions. https://doi.org/10.1103/physrevb.58.r10100

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