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

TL;DR

This study investigates how different spin structures affect the Fermi surface and pseudogap anisotropy in the t-t'-U Hubbard model, revealing doping-dependent stability and spectral features consistent with experimental ARPES data.

Contribution

It provides a comparative analysis of stripe and spiral spin structures' effects on Fermi surface topology and pseudogap behavior in the Hubbard model, highlighting doping-related stability differences.

Findings

Hole-doped models are unstable with respect to stripe and spiral structures.

Stripe phase shows quasi-one-dimensional Fermi surface segments at specific k-points.

Spiral structures exhibit polarization-dependent Fermi surface segments.

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=(\pi,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.