Chapter 4 deals with Frenkel excitons. These excitons are made of atomic excitations localized at a single lattice site. Starting from the crystal Hamiltonian, this chapter analyzes the various Coulomb processes and identifies the ones responsible for Frenkel exciton formation. It further considers electron spin states and orbital states and shows their importance in exciton physics. The last section provides tools—coboson commutator formalism and Shiva diagrams—for handling Frenkel exciton many-body effects. The study, in parallel, of Wannier and Frenkel excitons sheds light on the effect of the Pauli exclusion principle on correlated electron-hole pairs. This study in particular shows how closely Pauli blocking is associated with the dimensionless many-body parameter ruling exciton many-body effects, this understanding being supported by Cooper pairs.
Oxford Scholarship Online requires a subscription or purchase to access the full text of books within the service. Public users can however freely search the site and view the abstracts and keywords for each book and chapter.
If you think you should have access to this title, please contact your librarian.