Directed Collective Synchronization in Active Vortex Lattices

Collective dynamics of active matter systems holds great promise for the next generation of advanced tunable materials with high adaptability. However, because of their complex out-of-equilibrium nature, it has been challenging to precisely control the spatio-temporal organization and collective synchronization in active matter. Here, we show that, when energized by an external magnetic field, an ensemble of active magnetic rollers dispersed in micro-wells spontaneously evolves into vortex lattices. The presence of micro-wells facilitates not only the self-organization of active rollers into multi-vortex lattices but also the synchronization between the emergent vortices. In particular, we study the correlation between neighboring vortex-antivortex pair, resulting in an antiferromagnetic arrangement of the lattice, depending on the geometry of the wells. In addition it is shown that these synchronized vortex lattices have the ability to self-heal and to switch its chirality on-demand. Here we focus on the numerical simulations of such system using a contiuum model for the particle density which is coupled to shallow water fluid dyanmics.