title: Ultraviolet single-frequency coupled optofluidic ring resonator dye laser.
abstract: Ultraviolet single-frequency lasing is realized in a coupled optofluidic ring resonator (COFRR) dye laser that consists of a thin-walled capillary microfluidic ring resonator and a cylindrical resonator. The whispering gallery modes (WGMs) in each resonator couple to each other and generate single-frequency laser emission. Single-frequency lasing occurs at 386.75 nm with a pump threshold of 5.9 μJ/mm. The side-mode-suppression ratio (SMSR) is about 20 dB. Moreover, the laser emits mainly in two directions, and each of them has a divergence of only 10.5°.
authors.affiliation: Key Lab for Micro and Nanophotonic Structures (Ministry of Education), Department of Optical Science and Engineering, School of Information Science and Engineering, Fudan University, Shanghai 200433, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Tu
authors.forename: Xiang
authors.initials: X
authors.lastname: Wu
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Liying
authors.initials: L
authors.lastname: Liu
authors.forename: Lei
authors.initials: L
authors.lastname: Xu
mesh_terms: D004396:Coloring Agents / Q000737:chemistry*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007834:Lasers; D044085:Microfluidics / Q000295:instrumentation*; D012031:Refractometry / Q000295:instrumentation*; D014159:Transducers; D014466:Ultraviolet Rays
chemical_list: D004396:Coloring Agents