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Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
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On-Chip Glass Microspherical Shell Whispering Gallery Mode Resonators
Chenchen Zhang1, Alexander Cocking1, Eugene Freeman1
1School of Electrical Engineering and Computer Science, Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania, 16802, USA.
Scientific Reports
|November 4, 2017
Summary
Ultra-smooth, chip-scale glass microspheres act as high-Q optical resonators. These micro-resonators demonstrate high sensitivity for thermal sensing and microfluidic applications.
Area of Science:
- Optical physics
- Materials science
- Nanotechnology
Background:
- Optical micro-resonators are crucial for sensing applications.
- Fabricating high-quality micro-resonators with controlled properties remains a challenge.
Purpose of the Study:
- To develop and characterize on-chip spherical glass shells for optical resonance.
- To explore their potential as ultra-high sensitivity thermal and microfluidic sensors.
Main Methods:
- Fabrication of on-chip spherical glass shells with diameters in hundreds of micrometers and sub-micrometer wall thicknesses.
- Measurement of optical resonance modes and Q-factors.
- Characterization of temperature sensitivity.
- COMSOL modeling to understand shell thickness dependence.
Main Results:
- Fabricated resonators sustained optical resonance modes with Q-factors exceeding 50 million.
- Demonstrated temperature sensitivity of -1.8 GHz K-1.
- Showcased sensitivity to water filling and evaporation within the microspheres.
Conclusions:
- On-chip spherical glass shells are promising for high-Q optical resonance.
- These resonators can be configured as ultra-high sensitivity thermal sensors.
- The inner surface offers a platform for reproducible, chip-scale microfluidic sensor arrays.
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