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Updated: Jul 11, 2025
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Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
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Automatic Alignment Method for Controlled Free-Space Excitation of Whispering-Gallery Resonances
Davide D'Ambrosio1, Marialuisa Capezzuto1, Antonio Giorgini1
1Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica (INO), Via Campi Flegrei, 34 Comprensorio A. Olivetti, I-80078 Pozzuoli, Italy.
Sensors (Basel, Switzerland)
|November 14, 2023
Summary
Researchers developed an automated algorithm to excite whispering-gallery mode microresonators using free-space coupling. This method overcomes limitations of traditional fiber or prism coupling for applications in biosensing and nonlinear optics.
Area of Science:
- Optics and Photonics
- Micro-optics
- Nanophotonics
Background:
- Whispering-gallery mode (WGM) microresonators are widely used in biosensing and nonlinear optics.
- Conventional excitation methods (tapered fibers, prisms) have fabrication and access limitations.
- Free-space coupling offers an alternative but requires precise alignment.
Purpose of the Study:
- To develop and demonstrate an automated algorithm for exciting WGM microresonators.
- To overcome the alignment challenges associated with free-space coupling.
- To provide a more accessible and efficient method for WGM microresonator excitation.
Main Methods:
- Development of a novel algorithm for automated microresonator excitation.
- Implementation of a free-space coupling approach using a visible laser beam.
- Utilizing a spatial light modulator (SLM) and software control for precise beam manipulation.
- Experimental validation on a home-made silica microsphere.
Main Results:
- Successful demonstration of automated WGM excitation in a silica microsphere.
- Preliminary results show the efficacy of the developed algorithm.
- The method overcomes the need for complex manual alignment procedures.
- Potential for broader application in WGM microresonator-based systems.
Conclusions:
- The developed algorithm enables automated free-space coupling for WGM microresonators.
- This approach simplifies experimental setups and enhances accessibility.
- The method shows promise for advancing applications in sensing and nonlinear optics.
- Further research can optimize the algorithm for diverse microresonator systems.
Keywords:
Mie scatteringautomatic alignmentfree-space couplingspatial light modulatorwhispering-gallery mode resonatorMore Related Videos
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