Whispering gallery microsensors: a review

TL;DR

This review comprehensively summarizes optical whispering gallery mode microresonators, highlighting their sensing mechanisms, structures, applications, and future prospects in enhancing light-matter interactions for various sensors.

Contribution

It provides a detailed overview of WGM microresonator-based sensors, including recent advancements, sensing techniques, and applications, offering a valuable resource for future research and development.

Findings

Enhanced light-matter interaction in WGM sensors

Diverse structures and microfluidic integration techniques

Applications in matter and field sensing

Abstract

Optical whispering gallery mode (WGM) microresonators, confining resonant photons in a microscale resonator for long periods of time, could strongly enhance light-matter interaction, making it an ideal platform for all kinds of sensors. In this paper, an overview of optical sensors based on WGM microresonators is comprehensively summarized. First, the fundamental sensing mechanisms as well as several recently developed enhanced sensing techniques are introduced. Then, different types of WGM structures for sensing as well as microfluidics techniques are summarized. Furthermore, several important sensing parameters are discussed. Most importantly, a variety of WGM sensing applications are reviewed, including both traditional matter sensing and field sensing. Last, we give a brief summary and perspective of the WGM sensors and their role in future applications.