Superdiffusion induced by a long-correlated external random force

MARCELO DESPÓSITO

PHYSICAL REVIEW E

AMER PHYSICAL SOC

Año: 2011 vol. 84 p. 1 - 8

1539-3755

We consider a particle immersed in a thermal reservoir and simultaneously subjected to anexternal random force that drives the system to a non equilibrium situation. Starting from aLangevin equation description we derive exact expressions for the mean square displacement and the velocity autocorrelation function of the diffusing particle. An effective temperature is introduced to characterize the deviation from the internal equilibrium situation.Using a power-law force autocorrelation function, the mean square displacement and the velocityautocorrelation function are analytically obtained in terms of Mittag-Leffler functions. In this case,we show that the present model exhibits a superdiffusive regime as a consequence of the competition between passive and active processes.