Non-equilibrium Langevin dynamics of optical solitons: Raman dissipation, radiative decay, and the frequency-jitter spectrum

Modeling the Raman response as a damped oscillator's Green's function gives a matching dissipation kernel and a fluctuation-dissipation noise kernel. The exact scattering solution yields a closed-form radiative recoil, verified against direct propagation, that self-limits for ordinary fiber dispersion, and a noise crossover near a third-order-dispersion parameter of 0.13.

The resulting four-term timing-jitter formula raises the predicted jitter by 1.8 to 4.7 times for 50-100 fs pulses, and the same framework predicts an independently measured Raman-scattering coefficient to within 30%.</p>