Half-filled stripes in the t-t-U Hubbard model
نویسندگان
چکیده
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 nextto 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 ≃ −0.3 appropriate for YBa2Cu3O6+δ .
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