We present a comprehensive overview of sensor technology exploiting optical whispering
gallery mode (WGM) resonances. After a short introduction we begin by detailing the …

Optical whispering-gallery mode (WGM) microresonators, confining resonant photons in a
microscale volume for long periods of time, strongly enhance light-matter interactions …

High quality-factor (Q) optical resonators are a key component for ultra-narrow linewidth
lasers, frequency stabilization, precision spectroscopy and quantum applications. Integration …

On-chip optical resonators have the promise of revolutionizing numerous fields, including
metrology and sensing; however, their optical losses have always lagged behind those of …

Several types of sensors used in physics are based on the detection of splittings of resonant
frequencies or energy levels. We propose here to operate such sensors at so-called …

Detection of nanoscale objects is highly desirable in various fields such as early‐stage
disease diagnosis, environmental monitoring and homeland security. Optical microcavity …

We show that topologically protected defect states can exist in open (leaky or lossy) systems
even when these systems are topologically trivial in the closed limit. The states appear from …

Optical microcavities that confine light in high-Q resonance promise all of the capabilities
required for a successful next-generation microsystem biodetection technology. Label-free …

Whispering gallery mode (WGM) optical microresonators have attracted intense interests in
the past decades. The combination of high quality factors (Q) and small mode volumes of …

Optical whispering‐gallery mode (WGM) microcavities featuring ultrahigh Q factors and
small mode volumes enhance significantly the interaction between light and matter …