Two-polaron energy diffusion in a one-dimensional lattice of hydrogen bounded peptide units

Vincent J.C. Pouthier (1)

1 LPM - Laboratoire de Physique Moléculaire (UMR 6624)

A generalized Pauli master equation is established for describing the vibrational energy flow in a 1D lattice of hydrogen bounded peptide units. A Lang-Firsov transformation is applied so that the relevant excitations are small polarons corresponding to vibrational excitons dressed by virtual phonons. A special attention is thus paid to characterize the energy transfer mediated by two polarons. At biological temperature, it is shown that the polaron-phonon coupling is sufficiently strong to prevent any coherent motion. The polaron-polaron interaction occurring in such a nonlinear lattice does not affect the long time behavior of the energy flow which results from the diffusion of two independent polarons.

Mots clés: Nonlinear lattice; proteins; bi-polaron; energy diffusion

Domaines: Biophysique [physics.bio-ph]

Vincent J.C. Pouthier. Two-polaron energy diffusion in a one-dimensional lattice of hydrogen bounded peptide units. 2006. ⟨hal-00114696⟩