Delocalized vibrations in classical random chains

Normal modes of one-dimensional disordered chains with two couplings, one of them assigned at random to pairs in an otherwise perfect chain, are investigated. We diagonalize the dynamical matrix to find the normal modes and to study their spatial extent. Multifractal analysis is used to discern clea...

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Detalles Bibliográficos
Autores: Domínguez-Adame Acosta, Francisco, Maciá Barber, Enrique Alfonso, Sánchez, Angel
Tipo de recurso: artículo
Fecha de publicación:1993
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/59400
Acceso en línea:https://hdl.handle.net/20.500.14352/59400
Access Level:acceso abierto
Palabra clave:538.9
Random-dimer model
Conducting polymers
Localization
Absence
Física de materiales
Descripción
Sumario:Normal modes of one-dimensional disordered chains with two couplings, one of them assigned at random to pairs in an otherwise perfect chain, are investigated. We diagonalize the dynamical matrix to find the normal modes and to study their spatial extent. Multifractal analysis is used to discern clearly the localized or delocalized character of vibrations. In constrast to the general viewpoint that all normal modes in one dimensional random chains are localized, we find a set of extended modes close to a critical frequency, whose number increases with the system size and becomes independent of the defect concentration.