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Half-filled stripes in the t-t'-U Hubbard model

M. Raczkowski·A. M. Oles·R. Fresard
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Abstract

Using a self-consistent Hartree-Fock approximation we investigate the relative stability of various stripe phases in the extended $t$-$t'$-$U$ Hubbard model. One finds that a negative ratio of next- to nearest-neighbor hopping $t'/t<0$ expells holes from antiferromagnetic domains and reinforces the stripe order. Therefore the half-filled stripes not only accommodate holes but also redistribute them so that the kinetic energy is gained, and these stripes take over in the regime of $t'/t\simeq -0.3$ appropriate for YBa$_2$Cu$_3$O$_{6+δ}$.

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M. Raczkowski, A. M. Oles, R. Fresard. 2005-11-04. Half-filled stripes in the t-t'-U Hubbard model. https://doi.org/10.1002/pssb.200562403

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