Properties of electrostatically-driven granular medium: Phase transitions and charge transfer

The experimental and theoretical study of electrostatically driven granular material are reported. It is shown that the charged granular medium undergoes a hysteretic first order phase transition from the immobile condensed state (granular solid) to a fluidized dilated state (granular gas) with a changing applied electric field. In addition a spontaneous precipitation of dense clusters from the gas phase and subsequent coarsening - coagulation of these clusters is observed. Molecular dynamics simulations shows qualitative agreement with experimental results.