Packaged Droplet Microresonator for Thermal Sensing with High Sensitivity

Area of Science:

• Optics and Photonics
• Materials Science
• Sensing Technology

Background:

• Whispering gallery mode (WGM) microcavities, particularly liquid droplet and quasi-droplet types, show promise for sensing due to enhanced light-liquid interaction.
• Practical applications are hindered by the inherent fragility of these structures and liquid evaporation.

Purpose of the Study:

• To develop stable, packaged quasi-droplet and droplet microcavities for high-sensitivity thermal sensing.
• To present a quantified definition of quasi-droplet microcavities and analyze their optical properties.

Main Methods:

• Mie theory was employed to analyze sensitivity and electromagnetic field distribution.
• Stable, packaged droplet and quasi-droplet microcavities were fabricated.
• Dye material was doped into the liquid for lasing capabilities.

Main Results:

• A quantified definition for quasi-droplet microcavities was established.
• Packaged microcavity sensors demonstrated high thermal sensitivity up to 205.3 pm/°C.
• The fabricated devices exhibited mechanically robust properties.

Conclusions:

• Stable, packaged optofluidic microresonators offer a promising solution for thermal sensing.
• The developed microcavity sensors are suitable for future integrated photonic devices due to their sensitivity, ease of fabrication, and robustness.