Excitons in the strong coupling limit of the one-dimensional extended Hubbard model

Journal article

Excitons in the strong coupling limit of the half-filled one-dimensional extended Hubbard model with 1/r interactions are studied. Unlike the situation for nearest neighbor interactions, where there is at most only one (doubly degenerate) bound state, a 1/r interaction results in an infinite number of doubly degenerate bound states. In the continuum limit the exciton states are one-dimensional hydrogenlike states, with binding energies ∼ 1/n2. The particle-hole separation grows rapidly with n as n2. The binding energies are reduced on a discrete lattice. However, for conjugated systems of interest, the discrete correction to the continuum limit are small. When the infinite onsite repulsion limit is relaxed the degenerate states split, forming a doublet of even and odd parity states.

Authors: Barford, W

• Publication status: Published
• Journal: Physical Review B
• Volume: 65
• Issue: 20
• Pages: 2051181-2051185
• Publication date: 2002-05-15
• DOI: 10.1103/PhysRevB.65.205118
• EISSN: 1095-3795
• ISSN: 1098-0121
• Language: English