Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published July 2007 | public
Journal Article

All-optical modulation by plasmonic excitation of CdSe quantum dots


Photonics is a promising candidate technology for information processing, communication and data storage. Essential building blocks, such as logic elements and modulators, have been demonstrated. However, because of weak nonlinear light–matter interactions, these components typically require high power densities and large interaction volumes, limiting their application in dense chip-based integration. A solution may be found in surface plasmon polaritons (SPPs), guided electromagnetic waves that propagate with high field confinement along a metal–dielectric interface. We demonstrate an all-optical modulator in which efficient interaction between two light beams at different wavelengths is achieved by converting them into co-propagating SPPs interacting by means of a thin layer of CdSe quantum dots (QDs). The high SPP field confinement and high QD-absorption cross-section enable optical modulation at low power densities (~10^2 W cm^(-2)) in micrometre-scale planar devices.

Additional Information

© 2007 Nature Publishing Group. Received 18 September 2006; accepted 11 May 2007; published 2 July 2007. The authors acknowledge financial support from AFOSR MURI No. FA9550-04-1-0434. Discussion and technical support from R. J. Walters, L. A. Sweatlock, T. Carmon, S. J. Kim and E. Marcora are also gratefully acknowledged.

Additional details

August 19, 2023
October 20, 2023