Noise induced phase separation in active systems: Creating patterns with noise

We study the flocking and pattern formations of active particles with a Vicsek-like model that includes a configuration dependent noise term. In particular, we couple the strength of the noise with both the local density and orientation of neighboring particles. Our results show that such a configuration dependent noise can lead to the appearance of large-scale ordered and disordered patterns, without the need for any complex alignment interactions. In particular, we obtain an ordered band or line state and a disordered active cluster, similar to that seen in the case of motility induced phase separation.