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Quality-factor enhancement of supermodes in coupled microdisks
M Benyoucef1, J-B Shim, J Wiersig
1Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstrasse 20, 01069 Dresden, Germany. m.benyoucef@physik.uni‐kassel.de
Optics Letters
|April 19, 2011
Summary
We studied optical modes in coupled semiconductor microdisks. A novel quality-factor splitting in same-order whispering gallery modes (WGMs) creates supermodes, useful for optical coupling applications.
Area of Science:
- Optics and Photonics
- Condensed Matter Physics
- Quantum Electrodynamics
Background:
- Whispering gallery modes (WGMs) are crucial for light confinement in microdisk resonators.
- Understanding mode behavior in coupled microdisk systems is essential for advanced optical devices.
Purpose of the Study:
- To investigate the optical modes and quality factors in coupled semiconductor microdisks.
- To analyze the behavior of whispering gallery modes (WGMs) in symmetric and asymmetric configurations.
- To explore the phenomenon of quality-factor splitting and its implications.
Main Methods:
- Experimental characterization of optical modes in coupled microdisk pairs.
- Theoretical analysis and numerical simulations of mode behavior.
- Investigation of both symmetric and asymmetric coupling configurations.
Main Results:
- Observed conventional crossing for coupled first- and second-order WGMs.
- Discovered quality-factor splitting for same-order WGMs, forming high- and low-quality supermodes.
- Validated experimental findings through numerical simulations based on optical interference.
Conclusions:
- Quality-factor splitting in coupled microdisks is a significant phenomenon.
- This splitting leads to the formation of distinct supermodes with varying quality factors.
- The findings can guide the design of microarchitectures for enhanced optical coupling in cavity quantum electrodynamics.
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