Transport of overdamped Brownian particles driven by ac forces and time-delayed feedback

Transport of the overdamped Brownian particles in an asymmetric periodic potential is investigated in the presence of ac driving forces and time-delayed feedback. Using Brownian dynamics simulations, we obtain the average velocity of the particles. We found that it is possible to enhance the average velocity remarkably through increasing the delay time. For a large value of the delay time, the average velocity becomes independent of the delay time. Especially, for small values of noise intensity, there exists a threshold value of noise intensity below which no directed transport can be obtained. We can also observe current reversals by changing the parameters.