Multiple four-wave mixing self-stability in optical fibers

The self-stability of multiple four-wave mixing (FWM) processes in the optical fibers is studied both theoretically and experimentally. The coupled-mode equations for the complex amplitudes of four waves are derived. The nonlinear interaction between four optical fields involves a single nondegenerate and two degenerate FWM processes in the third-order nonlinear mixings. The proposed models are compared to the conventional coupled-mode theory of FWM processes and are proven by the experiments. The energy conservation of four waves is achieved, and the power flow relationship between two pump waves and two created waves is obtained. The analytic solutions reveal the self-stability mechanism of multiple FWM processes. The self-stability prediction is experimentally testified by using a kind of photonic-crystal fiber, and such excellence can be applied to achieve dual-wavelength erbium-doped fiber lasers with the excellent uniformity and stability.