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Nodal-antinodal dichotomy and magic doping fractions in a stripe ordered antiferromagnet

Mats Granath
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Abstract

We study a model of a stripe ordered doped antiferromagnet consisting of coupled Hubbard ladders which can be tuned from quasi-one-dimensional to two-dimensional. We solve for the magnetization and charge density on the ladders by Hartree-Fock theory and find a set of solutions with lightly doped ``spin-stripes'' which are antiferromagnetic and more heavily doped anti-phase ``charge-stripes''. Both the spin- and charge-stripes have electronic spectral weight near the Fermi energy but in different regions of the Brillouin zone; the spin-stripes in the ``nodal'' region, near (π/2,π/2), and the charge-stripes in the ``antinodal'' region, near (π,0). We find a striking dichotomy between nodal and antinodal states in which the nodal states are essentially delocalized and two-dimensional whereas the antinodal states are quasi-one-dimensional, localized on individual charge-stripes. For bond-centered stripes we also find an even-odd effect of the charge periodicity which could explain the non-monotonous variations with doping of the low-temperature resistivity in LSCO

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Mats Granath. 2006-10-03. Nodal-antinodal dichotomy and magic doping fractions in a stripe ordered antiferromagnet. https://doi.org/10.1103/physrevb.74.245112

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