Fused Microknot Optical Resonators in Folded Photonic Tapers for in-Liquid Durable Sensing

Area of Science:

• Photonics and Sensor Technology
• Materials Science

Background:

• Optical microknot fibers (OMFs) utilize photonic resonances (PRs) for environmental sensing.
• The fragility and instability of OMFs in aqueous environments limit their practical application as sensors.

Purpose of the Study:

• To develop a method for enhancing the durability of OMFs for in-liquid sensing.
• To demonstrate persistent detection of volatile liquids using modified OMFs through multiple wetting-dewetting cycles.

Main Methods:

• Fabrication and electrical fusing of OMFs.
• Preparation of OMFs for in-liquid sensing applications.
• Testing OMFs in multiple wetting-dewetting cycles with volatile liquids.
• Quantification of phase shifts using a model relating to the ambient liquid.

Main Results:

• Electrical fusing significantly improves the durability and stability of OMFs in liquid environments.
• OMFs demonstrate persistent detection capabilities for volatile liquids over multiple cycles.
• Phase shifts are quantifiable and correlate with the properties of the ambient liquid.

Conclusions:

• Electrically fused OMFs provide a durable platform for in-liquid sensing.
• The developed method enables reliable and persistent detection of volatile compounds.
• This advancement broadens the application of OMF photonic resonances in harsh environments.