TY - JOUR

T1 - Pseudogaps in strongly correlated metals

T2 - A generalized dynamical mean-field theory approach

AU - Sadovskii, M. V.

AU - Nekrasov, I. A.

AU - Kuchinskii, E. Z.

AU - Pruschke, Th

AU - Anisimov, V. I.

PY - 2005/10/15

Y1 - 2005/10/15

N2 - We generalize the dynamical-mean field (DMFT) approximation by including into the DMFT equations some length scale ξ via a momentum dependent external self-energy Σk. This external self-energy describes nonlocal dynamical correlations induced by the short-ranged collective spin density wave-like antiferromagnetic spin (or the charge density wave-like charge) fluctuations. At high enough temperatures these fluctuations can be viewed as a quenched Gaussian random field with a finite correlation length. This generalized DMFT+Σk approach is used for the numerical solution of the weakly doped one-band Hubbard model with repulsive Coulomb interaction on a square lattice with the nearest and the next nearest neighbor hopping. The effective single impurity problem in this generalized DMFT+Σk is solved by the numerical renormalization group. Both types of the strongly correlated metals, namely: (i) The doped Mott insulator and (ii) the case of the bandwidth W U (U-value of the local Coulomb interaction) are considered. The densities of states, the spectral functions, and the angle resolved photoemission spectra calculated within the DMFT+Σk show a pseudogap formation near the Fermi level of the quasiparticle band.

AB - We generalize the dynamical-mean field (DMFT) approximation by including into the DMFT equations some length scale ξ via a momentum dependent external self-energy Σk. This external self-energy describes nonlocal dynamical correlations induced by the short-ranged collective spin density wave-like antiferromagnetic spin (or the charge density wave-like charge) fluctuations. At high enough temperatures these fluctuations can be viewed as a quenched Gaussian random field with a finite correlation length. This generalized DMFT+Σk approach is used for the numerical solution of the weakly doped one-band Hubbard model with repulsive Coulomb interaction on a square lattice with the nearest and the next nearest neighbor hopping. The effective single impurity problem in this generalized DMFT+Σk is solved by the numerical renormalization group. Both types of the strongly correlated metals, namely: (i) The doped Mott insulator and (ii) the case of the bandwidth W U (U-value of the local Coulomb interaction) are considered. The densities of states, the spectral functions, and the angle resolved photoemission spectra calculated within the DMFT+Σk show a pseudogap formation near the Fermi level of the quasiparticle band.

UR - http://www.scopus.com/inward/record.url?scp=29644445215&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.72.155105

DO - 10.1103/PhysRevB.72.155105

M3 - Article

AN - SCOPUS:29644445215

VL - 72

JO - Physical Review B - Condensed Matter and Materials Physics

JF - Physical Review B - Condensed Matter and Materials Physics

SN - 1098-0121

IS - 15

M1 - 155105

ER -