Collective motion of vibrated polar disks.
We experimentally study a monolayer of vibrated disks with a built-in polar asymmetry which enables them to move quasibalistically on a large persistence length. Alignment occurs during collisions as a result of self-propulsion and hard core repulsion. Varying the amplitude of the vibration, we observe the onset of large-scale collective motion and the existence of giant number fluctuations with a scaling exponent in agreement with the predicted theoretical value.
Deseigne
Julien
J
Service de Physique de l'Etat Condensé, CEA-Saclay, URA 2464 CNRS, 91191 Gif-sur-Yvette, France.
Dauchot
Olivier
O
Chaté
Hugues
H