Interfacial Dripping Faucet: Generating Monodisperse Liquid Lenses

We present a surface analog to a dripping faucet, where a viscous liquid slides down an immiscible meniscus. Periodic pinch-off of the dripping filament is observed, generating a succession of monodisperse floating lenses. We show that this interfacial dripping faucet can be described analogously to its single-phase counterpart, replacing surface tension by the spreading coefficient, and even undergoes a transition to a jetting regime. This liquid-liquid-gas system opens perspectives for the study of the dynamics of emulsions at interfaces.