Enhanced transmission stability of polarization solitons in birefringent fibres with an optical phase conjugator

An optical phase conjugator is used to enhance transmission stability of polarization solitons in highly birefringent fibres. Two polarization solitons form a breather in fibres with low birefringence firstly and the optical phase conjugator is used to make the spectra of polarization solitons converse, which results in the fact that the polarization soliton along the fast axis is compressed due to the strengthened self-phase modulation effect: Two polarization solitons are compressed further due to the cross-phase modulation effect. The enhanced nonlinear effects make the central peak frequencies of two polarization solitons shift to the larger range in opposite directions so that they trap each other fully to suppress the effect of birefringence.