Reversible ultrafast soliton switching in dual-core highly nonlinear optical fibers.

We experimentally investigate a nonlinear switching mechanism in a dual-core highly nonlinear optical fiber. We focus the input stream of femtosecond pulses on one core only, to identify transitions between inter-core oscillations, self-trapping in the cross core, and self-trapping of the pulse in the straight core. A model based on the system of coupled nonlinear Schrödinger equations provides surprisingly good agreement with the experimental findings.