Raman Self-Focusing and Soliton Propagation in an Atomic Vapor

We analyze the theory behind Raman soliton propagation and soliton interactions in an atomic medium and discuss recent related experimental results. We use two strong lasers to drive a Raman transition in $^{87}$Rb and create a maximally coherent state; this coherence causes the beams to self-focus or self-defocus. A Raman soliton forms when the free-space diffraction is exactly cancelled by the self-focusing effect. We present our recent experimental observations of self-focusing and self-defocusing in this system, the first steps toward atomic Raman solitons.