Wgm Optical Resonators
Wgm Optical Resonators - Related Videos
08:53
Label-free Single Molecule Detection Using Microtoroid Optical Resonators
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Cited by 32 •
2015
We have developed a label-free biosensing system based on optical resonator technology known as Frequency Locking Optical Whispering Evanescent Resonator (FLOWER) that is capable of detecting single molecules in solution. Here the procedures behind this work are described and presented.
08:06
Fabrication of Polymer Microspheres for Optical Resonator and Laser Applications
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Cited by 3 •
2017
Protocols for the synthesis of microspheres from polymers, the manipulation of microspheres, and micro-photoluminescence measurements are presented.
12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
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Cited by 35 •
2013
The customized techniques developed in our lab to build microwave photonics systems based on ultra-high Q whispering gallery mode resonators are presented. The protocols to obtain and characterize these resonators are detailed, and an explanation of some of their applications in microwave photonics is given.
09:46
Fabrication and Characterization of High-Q Silicon Nitride Membrane Resonators
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Cited by 1 •
2025
This article traces the life cycle of a silicon nitride membrane resonator, from design through fabrication to characterization.
09:39
Optical Biosensing
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2023
Optical biosensors utilize light to detect the binding of a target molecule. These sensors can utilize a label molecule, which produces a measurable signal such as fluorescence, or these sensors can be label-free and use the changes in optical properties, such as refractive index, to sense for the binding of the target molecule. This video introduces both label and label-free optical biosensors, demonstrates their use in the laboratory, and shows some applications of the technology.
FAQs
At the curved dielectric boundary, light undergoes repeated total internal reflection and remains circulating rather than escaping. Resonance occurs only when the optical path length matches the condition needed for the circulating field to reinforce itself. Those allowed wavelengths appear as narrow spectral features, providing a precise optical signal that can be monitored for changes in the resonator’s surroundings.
A high quality factor produces narrow resonance features, making small wavelength changes easier to resolve. A small mode volume concentrates the optical field within a limited region, supporting strong interaction with nearby material. Together, these properties increase sensitivity to local refractive-index changes caused by biomolecular binding, cellular material, pathogens, or altered chemical composition.
Material near the circulating optical mode changes the local refractive index, which shifts the wavelengths that satisfy the resonance condition. Binding events or changes in chemical composition can therefore be observed as movements of narrow spectral features rather than by adding a fluorescent or other label. The shift provides an optical readout of the local environment.
Curved dielectric structures provide the boundary needed for light to circulate through repeated total internal reflection. Microspheres, microtoroids, and microdisks are examples of geometries that can support these modes when light is coupled into them. Their specific shapes provide different physical platforms for implementing the same resonance-based sensing principle in bioengineering systems.
A typical workflow couples light into a dielectric resonator, identifies the narrow spectral features associated with its resonant wavelengths, and then observes how those features change after the surrounding sample is introduced. Biomolecular binding, cells, pathogens, or chemical changes can produce refractive-index-dependent shifts. Researchers interpret the spectral response as evidence of changes near the optical mode.
Integrating the resonator with a microfluidic system allows samples and changing chemical environments to be brought into contact with the sensing region in a compact format. This combination can support real-time observation while reducing the size of the overall platform. In bioengineering, it is relevant to diagnostic systems and studies of cellular or molecular interactions.
These resonators support label-free detection of biomolecular binding, cells, pathogens, and changes in chemical composition. Their narrow spectral response, high quality factors, and small mode volumes make them useful when small local refractive-index changes must be monitored. Coupling the devices to microfluidics further supports compact diagnostic platforms and real-time investigations of biological interactions.