Skyrmion ratchet in funnel geometries

Using a particle-based model, we simulate the behavior of skyrmion under influence asymmetric funnel geometries and ac driving at zero temperature. We specifically investigate possibilities for controlling motion by harnessing ratchet effect. Our results show that as amplitude unidirectional drive is increased, can be set into along either easy or hard direction depending on direction. When parallel to axis, flows in its average velocity quantized. In contrast, when perpendicular Magnus-induced effect occurs, moves with constant velocity. For biharmonic equal both directions, observe reentrant pinning phase where vanishes. drives, exhibits combination effects move configuration drives. These indicate it possible achieve controlled using geometries, discuss ways which this could harnessed perform data transfer operations.