Nematic liquid crystal environment enables directional propulsion of spherical droplets representing aqueous dispersion of bacterial microswimmers[1]. Here we explore how the dynamics of active droplets can be controlled by patterning the nematic environment with singular and nonsingular director field. We use the plasmonic metamasks technique to pattern the director the form of non-singular disclinations. We demonstrate that interactions of the active droplet with the director gradients of the environment can be used to control propagation direction, speed, and locations of traps that stop propulsion.

1. Rajabi, M., Baza, H., Turiv, T. & Lavrentovich, O. D. Directional self-locomotion of active droplets enabled by nematic environment. Nat. Phys., doi:https://doi.org/10.1038/s41567-020-01055-5 (2020).