Manifestation of the Upper Hubbard band in the 2D Hubbard model at low electron density

Низкоразмерные структуры

Автор(и)

  • M.Yu. Kagan P.L. Kapitza Institute for Physical Problem, 2 ul. Kosygina, Moscow 119334, Russia
  • V.V. Val’kov Kirensky Institute of Physics, Akademgorodok, 50, bld. 38, Krasnoyarsk 660036, Russia
  • P. Woelfle Institute for Theoretical Condensed Matter physics, Karlsruhe Institute of Technology, Wolfgang-Gaede-Str., 1, Karlsruhe D-76131, Germany

DOI (Low Temperature Physics):


https://doi.org/10.1063/1.3670026

Ключові слова:

Hubbard model, Green-function, low electron density.

Анотація

We consider the 2D Hubbard model in the strong-coupling case (U >> W) and at low electron density (nd 2 << 1). We find an antibound state as a pole in the two-particle T-matrix. The contribution of this pole in the self-energy reproduces a two-pole structure in the dressed one-particle Green-function similar to the Hubbard-I approximation. We also discuss briefly the Engelbrecht-Randeria mode which corresponds to the pairing of two holes below the bottom of the band for U >> W and low electron density. Both poles produce nontrivial corrections to Landau Fermi-liquid picture already at low electron density but do not destroy it in 2D.

Downloads

Опубліковано

2011-08-22

Як цитувати

(1)
M.Yu. Kagan, V.V. Val&#8217;kov, and P. Woelfle, Manifestation of the Upper Hubbard band in the 2D Hubbard model at low electron density: Низкоразмерные структуры, Low Temp. Phys. 37, (2011) [Fiz. Nizk. Temp. 37, 1046-1052, (2011)] DOI: https://doi.org/10.1063/1.3670026.

Номер

Том 37 № 9-10 (2011)

Розділ

Статті

Завантаження

Дані завантаження ще не доступні.