Dynamics and stability of confined levitating droplets

Millimetric droplets have been shown to bounce on the surface of a vibrating liquid bath or “walk” by means of self-propulsion through a resonant interaction with their own wave field. When confined to an annular ring, we show that single droplets are observed to exhibit a random walk like behaviour, while the collective dynamics of one-dimensional droplet lattices exhibit canonical features of driven dissipative oscillator systems, namely out-of-phase oscillations and solitary wave propagation. Our experimental results are supported by a stability analysis of an accompanying theoretical model. Some open areas of investigation of potential interest to the dynamical and non-equilibrium systems community will be discussed in conclusion.