Jumping nanodroplets

Flat Au nanostructures on inert substrates like glass or graphite are illuminated by single intensive laser pulses with fluences above the Au melting threshold. The liquid structures produced in this way are far from their equilibrium shape, and as a consequence a dewetting process sets in: On a timescale of a few nano seconds the liquid contracts towards a sphere. During this contraction the center of mass moves upwards, which can lead to a detachment of the droplets from the surface due to inertia, resulting in velocities on the order of 10m/s for droplets with radii in the range of 100 nm.