Laser emission from individual droplets at wavelengths corresponding to morphology-dependent resonances.

Inelastic emission characteristics from individual ethanol droplets (60-microm diameter) containing Rhodamine 6G dye and pumped by a cw laser (514.5 nm) were investigated. Laser emission was confirmed by noting the spectral, temporal, and output-versus-input intensity behavior. The liquid-air boundary of the droplets provides the optical feedback at selected wavelengths corresponding to the morphology-dependent resonances of a spherical droplet.