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Abstract

Plasmonic bubbles are of great relevance in numerous applications, including catalytic reactions,
micro/nanomanipulation of molecules or particles dispersed in liquids, and cancer therapeutics. So far, studies
have been focused on bubble nucleation in pure liquids. Here we investigate plasmonic bubble nucleation in
ternary liquids consisting of ethanol, water, and trans-anethole oil, which can show the so-called ouzo effect. We
find that oil (trans-anethole) droplet plumes are produced around the growing plasmonic bubbles. The nucleation
of the microdroplets and their organization in droplet plumes is due to the symmetry breaking of the ethanol
concentration field during the selective evaporation of ethanol from the surrounding ternary liquids into the
growing plasmonic bubbles. Numerical simulations show the existence of a critical Marangoni number Ma (the
ratio between solutal advection rate and the diffusion rate), above which the symmetry breaking of the ethanol
concentration field occurs, leading to the emission of the droplet plumes. The numerical results agree with
the experimental observation that more plumes are emitted with increasing ethanol-water relative weight ratios
and hence Ma. Our findings on the droplet plume formation reveal the rich phenomena of plasmonic bubble
nucleation in multicomponent liquids and help to pave the way to achieve enhanced mixing in multicomponent
liquids in chemical, pharmaceutical, and cosmetic industries.