Abstract
Optical Whispering Gallery Mode (WGM) microresonators are an ideal platform for miniature and high sensitive sensors. They exhibit very small mode volumes and extremely high Q factors of the order of 106 - 109 providing a platform with low nonlinearity thresholds and low detection limits to environmental changes. Here we present and discuss some of the WGM-based applications we have been developing in our lab. Specifically, we present a WGM strain sensor based on a silica stretchable microsphere, with a Q factor of 108. Tension stress is applied along a microsphere with two fiber tails by pulling on one tail. Consequently, the microsphere's WGMs are shifted and the measurement may serve as a strain sensor. Based on this strain sensor, a WGM magnetic sensor is suggested where the mechanical response of a magnetostrictive material to a varying magnetic field applies the tension stress. In addition, a narrow linewidth laser source for these sensors is described here as well, where a multimode diode laser is locked to a single WGM of the microsphere via self-injection feedback from the microsphere. This optical locking is accompanied with a substantial spectral narrowing of the multimode diode laser.
Original language | English |
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Title of host publication | Fiber Lasers and Glass Photonics |
Subtitle of host publication | Materials through Applications III |
Editors | Maurizio Ferrari, Angela B. Seddon, Stefano Taccheo, Stefano Taccheo |
Publisher | SPIE |
ISBN (Electronic) | 9781510651609 |
DOIs | |
State | Published - 2022 |
Externally published | Yes |
Event | Fiber Lasers and Glass Photonics: Materials through Applications III 2022 - Virtual, Online Duration: 9 May 2022 → 20 May 2022 |
Publication series
Name | Proceedings of SPIE - The International Society for Optical Engineering |
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Volume | 12142 |
ISSN (Print) | 0277-786X |
ISSN (Electronic) | 1996-756X |
Conference
Conference | Fiber Lasers and Glass Photonics: Materials through Applications III 2022 |
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City | Virtual, Online |
Period | 9/05/22 → 20/05/22 |
Bibliographical note
Publisher Copyright:© 2022 SPIE.
Keywords
- Magnetic sensor
- Mechanical tuning
- Microsphere
- Optical laser locking
- Whispering Gallery Modes