Analytical approach to soliton ratchets in asymmetric potentials.
We use soliton perturbation theory and collective coordinate ansatz to investigate the mechanism of soliton ratchets in a driven and damped asymmetric double sine-Gordon equation. We show that, at the second order of the perturbation scheme, the soliton internal vibrations can couple effectively, in presence of damping, to the motion of the center of mass, giving rise to transport. An analytical expression for the mean velocity of the soliton is derived. The results of our analysis confirm the internal mode mechanism of soliton ratchets proposed in [Phys. Rev. E 65, 025602(R) (2002)].
Quintero
Niurka R
NR
Departamento de Física Aplicada I, E. U. P., Universidad de Sevilla, Virgen de Africa 7, 41011 Sevilla, Spain. niurka@euler.us.es
Sánchez-Rey
Bernardo
B
Salerno
Mario
M