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Quantum Electronics and Laser Science Conference

Fast light using multiple cascaded quantum-well semiconductor optical amplifiers

Piotr Konrad Kondratko, Hui Su, Shun Lien Chuang

Published May 1, 2007• 1 citation
Publisher

Abstract

We demonstrate variable fast light at room temperature using multiple cascaded quantum-well semiconductor optical amplifiers. Controllable delay is achieved both electrically and optically, or by varying the number of amplifiers or amplifier-to-amplifier attenuation.
DOI
10.1109/qels.2007.4431428

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Room temperature quantum-well semiconductor optical amplifier with large input power is utilized in both the absorption and gain regime as an optical group delay and advance (slow and fast light), respectively. Material resonance created by coherent population oscillation and four wave mixing is tuned by electrical injection current, which in turn controls the speed of light. The four-wave mixing and population oscillation model explains the slow-to-fast light switching. Experimentally, the scheme achieves 200 degrees phase shift at 1 GHz, which corresponds to 0.56 delay-bandwidth product. The device presents a feasible building block of a multi-bit optical buffer system.