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Physical Review A

Gain-assisted superluminal optical solitons at very low light intensity

Guoxiang Huang, Chao Hang, L. Deng

Published Jan 30, 2008• 47 citations
Publisher

Abstract

We show the possibility of generating gain-assisted superluminal optical solitons in a room-temperature three-state active Raman gain medium. We demonstrate both analytically and numerically that under appropriate conditions a signal field of very low intensity can evolve into a stable shape-preserving wave form that propagates with superluminal velocity. Shape recovery of superluminal solitons after collision is also demonstrated numerically.

DOI
10.1103/physreva.77.011803

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We propose a scheme to generate vector optical solitons in a four-level active-Raman-gain medium. We show that this scheme, which is fundamentally different from that using optical fibers and that via electromagnetically induced transparency, is capable of achieving robust vector optical solitons with superluminal propagating velocity. We demonstrate that such vector optical solitons can be generated at room temperature and with very low light intensity. We investigate also the interaction between two superluminal vector optical solitons and point out that their elastic and inelastic colliding properties can be used to design rapidly responding optical soliton switching and logic gates.
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