Abstract

The spectacular experimental demonstration of slowing light to cyclist speed in an ultra-cold atomic gas has spurred a significant interest in exploring the physics and applications of this phenomenon. Important applications that are foreseen include all-optical buffering, true time delays and filters for microwave photonics, as well as increased material nonlinearities for improved sensor elements. We have pursued the realization of slow light in semiconductor waveguides by using the physical effect of coherent population oscillations (CPO), which was demonstrated in Ruby crystals [1]. By exploiting wave mixing effects mediated by the coherent oscillation of the carrier density in a semiconductor waveguide, one can thus change the group velocity of light propagating in the waveguide. Due to the small, and to some extent controllable, carrier lifetime in semiconductors, this effect can be realized within GHz bandwidths, which is to be contrasted with the Hz to MHz bandwidths found in crystals and cold atomic gasses. Furthermore, one can utilize semiconductor fabrication technology to realize compact and integrated structures that optimize certain performances.

© 2007 IEEE