Quartic lattice interactions, soliton-like excitations, and electron pairing in one-dimensional anharmonic crystals

• Autor(a) principal: Velarde, M. G.
• Data de Publicação: 2012
• Outros Autores: Brizhik, L., Chetverikov, A. P., Cruzeiro, Leonor, Ebeling, W., Röpke, G.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.1/3572
• topic: Electron pairing; Bisolectron; Anharmonic lattice; Solectron

In this study, it is shown that two added, excess electrons with opposite spins in one-dimensional crystal lattices with quartic anharmonicity may form a bisolectron, which is a localized bound state of the paired electrons to a soliton-like lattice deformation. It is also shown that when the Coulomb repulsion is included, the wave function of the bisolectron has two maxima, and such a state is stable in lattices with strong enough electron (phonon/soliton)–lattice coupling. Furthermore, the energy of the bisolectron is shown to be lower than the energy of the state with two separate, independent electrons, as even with account of the Coulomb repulsion the bisolectron binding energy is positive.