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Quantum Monte Carlo simulations of the half-filled two-dimensional Kondo lattice model

F. F. Assaad
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Abstract

The 2D half-filled Kondo lattice model with exchange J and nearest neighbor hopping t is considered. It is shown that this model belongs to a class of Hamiltonians for which zero-temperature auxiliary field Monte Carlo methods may be efficiently applied. We compute the staggered moment, spin and quasiparticle gaps on lattice sizes up to 12 X 12. The competition between the RKKY interaction and Kondo effect leads to a continuous quantum phase transition between antiferromagnetic and spin-gaped insulators. This transition occurs at J/t = 1.45 \pm 0.05.

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F. F. Assaad. 1999-04-13. Quantum Monte Carlo simulations of the half-filled two-dimensional Kondo lattice model. https://doi.org/10.1103/physrevlett.83.796

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