Optical microfibers integrated with evanescent field triggered self-growing polymer nanofilms

Area of Science:

• Photonics
• Materials Science
• Nanotechnology

Background:

• Hybrid optical fibers are crucial for integrated photonic devices.
• Existing fabrication methods for functionalized microfibers can be complex.

Purpose of the Study:

• To propose and fabricate a novel hybrid microfiber waveguide.
• To demonstrate a new method for creating polymer nanofilms on microfibers using light.
• To explore the potential of these hybrid microfibers for sensing applications.

Main Methods:

• Fabrication of hybrid microfiber waveguides using a self-growing polymer nanofilm technique triggered by evanescent light.
• Optimization of nanofilm roughness by controlling laser power and exposure duration.
• Characterization of optical properties, including transmission loss across a wide wavelength range.

Main Results:

• Successful growth of a ~50 nm polymer nanofilm on microfibers up to 15 mm in length.
• Optimized nanofilm roughness achieved through controlled laser parameters.
• Low total transmission loss (< 2 dB) over a broad wavelength range.
• Demonstrated relative humidity (RH) sensing capabilities.

Conclusions:

• The proposed fabrication method offers a novel route to create functional hybrid microfibers.
• The hybrid polymer nanofilm microfiber waveguides exhibit promising performance for RH sensing.
• The fabrication technique is adaptable for incorporating various photopolymer materials.