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Anisotropy on the Fermi Surface of the Two-Dimensional Hubbard Model

Y. Otsuka·Y. Morita·Y. Hatsugai
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Abstract

We investigate anisotropic charge fluctuations in the two-dimensional Hubbard model at half filling. By the quantum Monte Carlo method, we calculate a momentum-resolved charge compressibility $κ(\bm{k}) = {d < n(\bm{k}) >}/{d μ}$, which shows effects of an infinitesimal doping. At the temperature $T \sim {t^2}/{U}$, $κ(\bm{k})$ shows peak structure at the $(\pm π/2,\pm π/2)$ points along the $|k_x| + |k_y| = π$ line. A similar peak structure is reproduced in the mean-filed calculation for the d-wave pairing state or the staggered flux state.

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Y. Otsuka, Y. Morita, Y. Hatsugai. 2002-06-16. Anisotropy on the Fermi Surface of the Two-Dimensional Hubbard Model. https://doi.org/10.1103/physrevb.66.073109

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