Dynamics of microflow at the plasma–liquid interface

We study the interaction of microplasma with viscous liquid in a narrow gap. The reduced surface tension and viscosity of the liquid droplet from local plasma-heating induce a radial fingering. The introduced methodology enables spatially and temporally resolved quantification of dissipated power density and of resulting velocity of the advancing plasma–liquid interface. For two plasma power scenarios, we demonstrate how the irregular distribution of the two parameters leads to microflow, interface stretching, and to primary droplet fragmentation via capillary instability and end pinching.