Colloidal quantum dots in all-dielectric high-Q pillar microcavities
Matthias Kahl1, Tim Thomay, Verena Kohnle
1Department of Physics and Center for Applied Photonics, University of Konstanz, D-78464 Konstanz, Germany.
Nano Letters
|August 29, 2007
Summary
We fabricated all-dielectric optical resonators with embedded quantum dots for light emission. Elliptical resonators demonstrated higher quality factors than circular ones, improving light confinement.
Area of Science:
- Nanophotonics
- Quantum Optics
- Materials Science
Background:
- All-dielectric optical resonators are crucial for manipulating light at the nanoscale.
- Quantum dots (QDs) offer tunable light emission properties for integrated photonic devices.
Purpose of the Study:
- To fabricate and characterize all-dielectric optical pillar resonators with embedded quantum emitters.
- To investigate the effect of resonator geometry on optical performance and light confinement.
Main Methods:
- Focused ion beam milling was used to fabricate all-dielectric pillar resonators.
- Colloidal cadmium selenide/zinc sulfide (CdSe/ZnS) quantum dots and rods were embedded as light emitters.
- Optical characterization and a waveguide model were employed to analyze microcavity modes.
Main Results:
- Three-dimensional light confinement and distinct pillar microcavity modes were successfully observed.
- Experimental data showed excellent agreement with the waveguide model for mode patterns and spectral positions.
- Elliptical cross-section cavities exhibited higher quality factors along the short axis compared to circular resonators of equivalent area.
Conclusions:
- All-dielectric optical pillar resonators with embedded quantum emitters can be fabricated with high quality factors.
- Resonator geometry significantly influences optical performance, with elliptical shapes offering advantages in light confinement.
- These findings contribute to the development of advanced photonic devices for light emission and manipulation.
