Theoretical and experimental investigation of all-optical switching based on cascaded LPFGs separated by an erbium-doped fiber

Abstract

A new all-optical switching device, which is constructed by connecting an erbium-doped fiber with two symmetrical long-period fiber gratings (EDF-LPFGs), is demonstrated. The performance of EDF-LPFGs switching has been investigated based on cross-phase modulation under different parameters. The theoretical analysis shows that the threshold switching power is inverse proportional to the nonlinear coefficient of the erbium-doped fiber, and is proportional to the effective area of the erbium-doped fiber and absorption coefficient. Moreover, the switching power as low as 36 mW and high extinction ratio of 18 dB are obtained in our experiment. Good agreement between the theoretical and experimental results indicate that EDF-LPFGs switching is a new design in support of switching power reduction.