Highly Accurate Pneumatically Tunable Optofluidic Distributed Feedback Dye Lasers

• Published in: Micromachines (Basel) Vol. 15; no. 1; p. 68
• Main Authors: Feng, Hongtao, Zhang, Jiaxin, Shu, Weiliang, Bai, Xiaosong, Song, Liang, Chen, Yan
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 29.12.2023; MDPI
• Subjects: Channels; Coherent light; Deformation; Distributed feedback lasers; Dye lasers; Dyes; High resolution; Integrated approach; Lab-on-a-chip; Lasers; Lasing; Light; Light sources; Microfluidics; Multilayers; optofluidic chip; photonic device; Physiology; Portable equipment; Thin films; tunable DFB laser; Tunable lasers; Tuning; Vacuum chambers; Waveguides; United States > US; Japan; tunable DFB laser; optofluidic chip; photonic device
• ISSN: 2072-666X; 2072-666X
• DOI: 10.3390/mi15010068

Optofluidic dye lasers integrated into microfluidic chips are promising miniature coherent light sources for biosensing. However, achieving the accurate and efficient tuning of lasers remains challenging. This study introduces a novel pneumatically tunable optofluidic distributed feedback (DFB) dye laser in a multilayer microfluidic chip. The dye laser device integrates microfluidic channels, grating structures, and vacuum chambers. A second-order DFB grating configuration is utilized to ensure single-mode lasing. The application of vacuum pressure to the chambers stretches the soft grating layer, enabling the sensitive tuning of the lasing wavelength at a high resolution of 0.25 nm within a 7.84 nm range. The precise control of pressure and laser tuning is achieved through an electronic regulator. Additionally, the integrated microfluidic channels and optimized waveguide structure facilitate efficient dye excitation, resulting in a low pump threshold of 164 nJ/pulse. This pneumatically tunable optofluidic DFB laser, with its high-resolution wavelength tuning range, offers new possibilities for the development of integrated portable devices for biosensing and spectroscopy.