Single mode coupled optofluidic ring resonator dye lasers

The authors demonstrate the single mode dye laser from a coupled optofluidic ring resonator that consists of a cylindrical ring resonator fused onto the inner surface of a thin-walled capillary ring resonator. The whispering gallery modes in each ring resonator interact strongly and utilize the Vernier effect to generate single mode laser emission. The lasing threshold is 3.0 μJ/mm2. The light can be coupled out through an optical taper in contact with the capillary.