title: Monolithic optofluidic ring resonator lasers created by femtosecond laser nanofabrication.
abstract: We designed, fabricated, and characterized a monolithically integrated optofluidic ring resonator laser that is mechanically, thermally, and chemically robust. The entire device, including the ring resonator channel and sample delivery microfluidics, was created in a block of fused-silica glass using a 3-dimensional femtosecond laser writing process. The gain medium, composed of Rhodamine 6G (R6G) dissolved in quinoline, was flowed through the ring resonator. Lasing was achieved at a pump threshold of approximately 15 μJ mm(-2). Detailed analysis shows that the Q-factor of the optofluidic ring resonator is 3.3 × 10(4), which is limited by both solvent absorption and scattering loss. In particular, a Q-factor resulting from the scattering loss can be as high as 4.2 × 10(4), suggesting the feasibility of using a femtosecond laser to create high quality optical cavities.
authors.affiliation: Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA. xsfan@umich.edu.
authors.forename: Hengky
authors.initials: H
authors.lastname: Chandrahalim
authors.forename: Qiushu
authors.initials: Q
authors.lastname: Chen
authors.forename: Ali A
authors.initials: AA
authors.lastname: Said
authors.forename: Mark
authors.initials: M
authors.lastname: Dugan
authors.forename: Xudong
authors.initials: X
authors.lastname: Fan
mesh_terms: D056656:Lab-On-A-Chip Devices; D007834:Lasers; D012235:Rhodamines / Q000737:chemistry*
chemical_list: D012235:Rhodamines; C026188:rhodamine 6G