Multi-wavelength coherent random laser in bio-microfibers

Area of Science:

• Biomaterials Science
• Optics and Photonics
• Nanotechnology

Background:

• Silk fibroin, a natural protein, offers unique optical and mechanical properties.
• Random lasers, utilizing scattering for feedback, present an alternative to traditional laser designs.
• Electrospinning is a versatile technique for fabricating microfiber structures.

Purpose of the Study:

• To fabricate disordered bio-microfiber structures from pure silk protein using electrospinning.
• To investigate the random lasing properties of these silk fibroin fibers.
• To explore the potential applications of silk-based random lasers as tunable light sources and in speckle-free imaging.

Main Methods:

• Extraction of pure silk protein from Bombyx mori silks.
• Fabrication of bio-microfiber structures via electrospinning technology.
• Characterization of coherent random lasing emission and wavelength tunability.

Main Results:

• Achieved coherent random lasing emission with a low threshold in silk fibroin fibers.
• Demonstrated wavelength tunability of the random lasing emission over a 33 nm range by controlling pump location and scattering strengths.
• Successfully applied the bio-microfiber random lasers as a low-coherence light source for speckle-free imaging.

Conclusions:

• Pure silk protein can be effectively fabricated into bio-microfiber random lasers.
• Silk-based random lasers offer tunable spectral output and potential for broad spectral light sources when doped.
• These bio-microfiber random lasers show promise for advanced imaging techniques like speckle-free imaging.