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Influence of spin structures and nesting on Fermi surface and a pseudogap anisotropy in t-t'-U Hubbard model

A A Ovchinnikov·M Ya Ovchinnikova
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Abstract

Influence of two type of spin structures on the form of the Fermi surface (FS) and a photoemission intensity map is studied for t-t'-U Hubbard model. Mean field calculations are done for the stripe phase and for the spiral spin structure. It is shown, that unlike a case of electron doping, the hole-doped models are unstable with respect to formation of such structures. The pseudogap anisotropies are different for h- and e- doping. In accordance with ARPES data for La2SrxCuO4 the stripe phase is characterized by quasi-one-dimensional segments of FS at k=(π,0) and by suppression of spectral weight in diagonal direction. It is shown that spiral structures display the polarisation anisotropy: different segments of FS correspond to electros with different spin polarisations.

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A A Ovchinnikov, M Ya Ovchinnikova. 2003-05-29. Influence of spin structures and nesting on Fermi surface and a pseudogap anisotropy in t-t'-U Hubbard model. https://doi.org/10.1134/1.1705707

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