"Destruction" of the fermi surface due to pseudogap fluctuations in strongly correlated systems

Details "Destruction" of the fermi surface due to pseudogap fluctuations in strongly correlated systems "Destruction" of the fermi surface due to pseudogap fluctuations in strongly correlated systems

2005-06-09

arxiv.org/abs/cond-mat/0506215v1

JETP Letters 82 (2005) 198

Physics

Condensed Matter

Strongly Correlated Electrons

5 pages, 3 figures, jetpl.cls included

Scientific paper

10.1134/1.2121814

We generalize the dynamical - mean field theory (DMFT) by including into the DMFT equations dependence on correlation length of pseudogap fluctuations via additional (momentum dependent) self - energy. This self - energy describes non - local dynamical correlations induced by short - ranged collective SDW - like antiferromagnetic spin (or CDW - like charge) fluctuations. At high enough temperatures these fluctuations can be viewed as a quenched Gaussian random field with finite correlation length. This generalized DMFT+\Sigma_k approach is used for the numerical solution of the weakly doped one - band Hubbard model with repulsive Coulomb interaction on a square lattice with nearest and next nearest neighbour hopping. The effective single impurity problem is solved by numerical renormalization group (NRG). Both types of strongly correlated metals, namely (i) doped Mott insulator and (ii) the case of bandwidth W