Quantitatively mimicking wet colloidal suspensions with dry granular media

Athermal two-dimensional granular systems are exposed to external mechanical noise leading to
Brownian-like motion. Using tunable repulsive interparticle interaction, it is shown that the same
microstructure as that observed in colloidal suspensions can be quantitatively recovered at a
macroscopic scale. To that end, experiments on granular and colloidal systems made up of
magnetized particles as well as computer simulations are performed and compared. Excellent
agreement throughout the range of the magnetic coupling parameter Γ is found for the pair
distribution as well as the bond-orientational correlation functions. This finding opens new ways to
efficiently and very conveniently explore phase transitions, crystallization, nucleation, etc in confined
geometries.