Light-driven microswimmers: pushing, pulling and shaping materials from within
Artificial microswimmers or self-propelled colloidal particle systems are currently a subject of great interest in soft condensed matter for a variety of reasons. First, they present us with model systems to study the collective behavior of their more complex natural counterparts and they represent beautiful examples of out-of-equilibrium systems. Second, they can help us to understand how biofilms form and how bacteria move around in and shape their polymeric habitat.
One class of these artificial model systems moves actively by consuming chemical energy from its local environment. In this talk, I will introduce a novel self-propelled particle system in which we control the energy consumption by light and how we can reversibly switch the swimming direction between both sides of the particle in-situ using photocatalytic effects. Moreover, I will discuss the broad implications of reversing the swimming direction in combination with the propulsion strength of an individual swimmer in the collective behavior of both active systems and mixtures of active and passive particles. A few perspectives will be given on how these pushers and pullers may shape materials from within.