Entropic transport of active particles driven by a transverse ac force

• A transverse ac force strongly influence the transport of active particles.
• The direction of the transport can be reversed several times.
• Active particles with different self-propelled speeds can be separated.

Transport of active particles is numerically investigated in a two-dimensional period channel. In the presence of a transverse ac force, the directed transport of active particles demonstrates striking behaviors. By adjusting the amplitude and the frequency of the transverse ac force, the average velocity will be influenced significantly and the direction of the transport can be reversed several times. Remarkably, it is also found that the direction of the transport varies with different self-propelled speeds. Therefore, particles with different self-propelled speeds will move to the different directions, which is able to separate particles of different self-propelled speeds.