We have developed a stereo video rig able to track particles in three dimensions to study the gas-like phase of an experimental granular media system driven by contact charge electrophoresis. We...Show moreWe have developed a stereo video rig able to track particles in three dimensions to study the gas-like phase of an experimental granular media system driven by contact charge electrophoresis. We use the stereo set-up to simultaneously capture the granular media gas-like 2D dynamics and the particle motion in the perpendicular driven direction. We find that melting of the crystalline order happens when two particles anti-synchronize their oscillation phase, attract due to opposite sign charges, and collide. The repeated occurrence of such events establish a sustained mechanism of energy injection from the driven direction to the XY plane, resulting in a stationary dilute gas-like phase. We explore the change in dynamics upon an increase of the driving field and find that the dynamics of the gas-like phase are unchanged if re-normalized by the period of oscillation in the driven direction. The developed stereo system has proved itself as a robust and crucial advance in the experimental techniques used to explore the physics of driven media, opening the door to perform experiments fully capturing both the driven and horizontal dynamics.Show less
