"Circular Motion of Asymmetric Self-Propelling Particles" by Felix Kummel, Borge ten Hagen, Raphael Wittkowski, Ivo Buttinoni, Ralf Eichhorn, Giovanni Volpe, Hartmut Lowen and Clemens Bechinger Reference: Phys. Rev. Lett. 110, 198302 (2013); http://prl.aps.org/abstract/PRL/v110/i19/e198302 Observing the motion of micron-sized particles allows insight into how active matter organizes into complex dynamical structures. During the last decade many studies have investigated the dynamics of active microswimmers, where artificial flagella or thermophoretic and diffusiophoretic force leads to active motion. Most studies so far have investigated the dynamics of spherical and rodlike microswimmers. Such symmetrical microswimmers are just a crude approximation for real self-propelling microorganisms. In this talk, I will present the recent paper of Kummel et al., which experimentally and theoretically studies the motion of asymmetric L-shaped self-propelling particles in a viscous liquid. In the first part of my talk I will explain how these microswimmers are fabricated and how their self-propulsion is controlled. Then I will present experimental results. Kummel's experiments show that L-shaped particles perform circular motion in the presence of a propelling force, which is in contrast with spherical swimmers. In the last part of my talk I will present their theoretical model and its comparison with experimental observations.