2015/11/12 by Sonja Babel, S. Babel, Hartmut Löwen +3
Biochemistry, Genetics and Molecular Biology · Materials Science · Physics and Astronomy · #Bifurcation #Dynamics (music) #Harmonic #Hopf bifurcation #Hydrogels: synthesis, properties, applications #Instability #Magnetic field #Micro and Nano Robotics #Pickering emulsions and particle stabilization #Relaxation (psychology) #Trajectory #cond-mat.soft #physics.bio-ph
paper · pdf · doi:10.1209/0295-5075/113/58003
published as Europhys. Lett. 113, 58003 (2016) · 6 pages, 8 figures
arxiv created 2015/11/12 · openalex publication_date 2016/03/01 · arxiv updated 2016/04/12 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
In analogy to nanoscopic molecules that are composed of individual atoms, we consider an active "microswimmer molecule". It is made of three individual magnetic colloidal microswimmers that are connected by harmonic springs and interact hydrodynamically. In the ground state, they form a linear straight molecule. We analyze the relaxation dynamics for perturbations of this straight configuration. As a central result, with increasing self-propulsion, we observe an oscillatory instability in accord with a subcritical Hopf bifurcation scenario. It is accompanied by a corkscrew-like swimming trajectory of increasing radius. Our results can be tested experimentally, using, for instance, magnetic self-propelled Janus particles, supposably linked by DNA molecules.