Double Emulsion Optofluidic Microlasers

摘要

Double emulsion droplets have found diverse applications in biosensing, chemical synthesis, drug delivery, and highthroughputscreening and production. In this work, we demonstrate monodisperse double emulsion optofluidicmicrolasers with a dye-doped thin shell structure. In particular, robust generation of water-in-oil-in-water (W/O/W)double emulsion droplets in a hydrodynamic flow focusing microfluidic device is demonstrated. With carefularrangement of the three liquid components in the double emulsion, an optical microcavity is formed which supports thewhispering gallery modes (WGMs) that locate near the surface of the shell layer. Low-threshold lasing has beenachieved in W/O/W double emulsion droplets. Lasing emission from double emulsion droplets with different diameterand different shell layer thickness are characterized on the flow. Due to the high degree of control provided by themicrofluidic device, both droplet size and shell layer thickness can be conveniently tuned, and thus the lasing properties.The unique two-phase core-shell structure of the double emulsion droplets provides great flexibility and potential in thedevelopment of biosensing platform based on the optofluidic laser system demonstrated in this work, especially in thehigh-throughput bioanalysis.