Energy localization in the Peyrard-Bishop DNA model

• Autor(a) principal: De Luca, Jayme
• Data de Publicação: 2004
• Outros Autores: Drigo Filho, Elso [UNESP], Ponno, Antonio, Ruggiero, José Roberto [UNESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1103/PhysRevE.70.026213; http://hdl.handle.net/11449/225146

We study energy localization on the oscillator chain proposed by Peyrard and Bishop to model DNA. We search numerically for conditions with initial energy in a small subgroup of consecutive oscillators of a finite chain and such that the oscillation amplitude is small outside this subgroup on a long time scale. We use a localization criterion based on the information entropy and verify numerically that such localized excitations exist when the nonlinear dynamics of the subgroup oscillates with a frequency inside the reactive band of the linear chain. We predict a mimium value for the Morse parameter [Formula presented] (the only parameter of our normalized model), in agreement with the numerical calculations (an estimate for the biological value is [Formula presented]). For supercritical masses, we use canonical perturbation theory to expand the frequencies of the subgroup and we calculate an energy threshold in agreement with the numerical calculations. © 2004 The American Physical Society.