Premium
Cluster perturbation study of 1D electron–hole Hubbard model
Author(s) -
Asano Kenichi,
Nishida Takuto,
Ogawa Tetsuo
Publication year - 2008
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.200879807
Subject(s) - hubbard model , electron , physics , condensed matter physics , electron hole , cluster (spacecraft) , atomic physics , binding energy , perturbation theory (quantum mechanics) , fermi energy , perturbation (astronomy) , fermi gamma ray space telescope , interaction energy , quantum mechanics , superconductivity , molecule , computer science , programming language
We studied the quarter‐filled electron–hole Hubbard model of one dimension using the cluster perturbation method. We found that the ground states of this system are always insulating as long as the electron–hole attractive interaction has a finite value. The calculated density of states for the electron and hole is significantly renormalized by the interaction, and show energy gaps at the Fermi energy. These gaps are induced by the excitonic mechanism at U > U ′ and by the biexcitonic one at U < U ′, where U (> 0) denotes the electron–electron and hole–hole repulsive interaction, and U ′(< 0) denotes the electron–hole attractive interaction. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)