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Title: Pneumatically tunable optofluidic DFB dye laser using corrugated sidewalls

Polydimethylsiloxane-based optofluidics provides a powerful platform for a complete analytical lab-on-chip. Here, we report on a novel on-chip laser source that can be integrated with sample preparation and analysis functions. A corrugated sidewall structure is integrated into a microfluidic channel to form a distributed feedback (DFB) laser using rhodamine 6G dissolved in an ethylene glycol and water solution. Lasing is demonstrated with a threshold pump power of 87.9 µW, corresponding to a pump intensity of52.7mW/cm2. Laser threshold and output power are optimized with respect to rhodamine 6G concentration and core index and found to be in good agreement with a rate equation model. Additionally, the laser can be switched on and off mechanically using a pneumatic cell inducing positive pressure on the grating.

Authors:
; ; ; ;
Award ID(s):
1703058
Publication Date:
NSF-PAR ID:
10199288
Journal Name:
Optics Letters
Volume:
45
Issue:
21
Page Range or eLocation-ID:
Article No. 5978
ISSN:
0146-9592; OPLEDP
Publisher:
Optical Society of America
Sponsoring Org:
National Science Foundation
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