Organic photonic bandgap microcavities doped with semiconductor nanocrystals for room-temperature on-demand single-photon sources

Abstract

We report the first experimental observation of fluorescence from single semiconductor nanocrystals (colloidal quantum dots) in microcavities. In these room-temperature experiments we observed photon antibunching from single CdSe nanocrystals doped into a chiral one-dimensional photonic bandgap liquid-crystal microcavity. The chirality resulted in high-purity, circular polarization of definite handedness of the emitted single photons. We also report the fabrication of chiral microcavities for telecom wavelengths doped with PbSe nanocrystals as well as a solution-processed-polymer microcavity with a defect layer doped with CdSe nanocrystals between two distributed Bragg reflectors. These systems with their low host fluorescence background are attractive for on-demand single-photon sources for quantum information and communication.

Keywords:

• single-photon sources
• colloidal quantum dots
• microcavities

Acknowledgements

The University of Rochester authors acknowledge support by the NSF Award ECS-0420888 and EHR-0633621. L.J. Bissell thanks the Air Force for a SMART fellowship. The authors thank A. Lieb and L. Novotny for advice and help, Z. Shi and H. Shin for assistance and J. Dowling for providing better understanding of emitter fluorescence in CLC photonic bandgap structures. Queens College authors’ work was supported partly by the Army Research Office, Short Term Analytical Service Grant at Queens College–CUNY.