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Updated: Jun 22, 2026
12:21
Stimulated Stokes and Antistokes Raman Scattering in Microspherical Whispering Gallery Mode Resonators
Published on: April 4, 2016
Coupled spiral-shaped microdisk resonators with non-evanescent asymmetric inter-cavity coupling
Optics Express
|June 25, 2009
Summary
We demonstrate coupled spiral microdisk resonators with novel coupling for enhanced optical filtering. Mismatched resonators selectively boost extinction ratios up to 24 dB, preserving high-Q factors for advanced photonic devices.
Area of Science:
- Photonics
- Optical Engineering
- Materials Science
Background:
- Microdisk resonators are key components in integrated photonics.
- Achieving high extinction ratios in coupled resonators is crucial for optical filtering applications.
- Non-evanescent coupling methods offer potential for preserving resonance quality (Q-factor).
Purpose of the Study:
- To investigate coupled spiral-shaped microdisk resonators with non-evanescent asymmetric inter-cavity coupling.
- To analyze the transmission characteristics and modal field distributions of these coupled systems.
- To demonstrate selective enhancement of extinction ratios by introducing controlled asymmetry.
Main Methods:
- Finite-difference time-domain (FDTD) numerical simulations.
- Experimental fabrication and characterization of silicon nitride-on-silica microdisk resonators.
- Analysis of throughput and drop-port transmissions for counterclockwise (CCW) and clockwise (CW) modes.
Main Results:
- Reciprocal throughput-port transmissions for CCW and CW modes were observed.
- Input-port dependent drop-port transmissions and modal field distributions were confirmed.
- Identical coupled microdisks achieved ~20 dB extinction ratio.
- Slightly mismatched microdisks enhanced extinction ratio to ~24 dB for one split mode.
Conclusions:
- Non-evanescent coupling via seamlessly jointed notches preserves high-Q resonances.
- Controlled radius mismatch in coupled spiral microdisks enables selective extinction ratio enhancement.
- These findings are significant for developing advanced optical filters and devices.
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