增益调制型波长转换中,为得到转换后信号最大的消光比(ER),信号光波长应该比半导体光放大器(SOA)的小信号增益峰值波长长.采用分段模型,考虑了SOA中增益谱的不对称性以及增益峰值波长随载流子密度的漂移,深入研究了信号光功率,ER,参考光功率,波长以及SOA注入电流对选择信号光波长λpk,s以及消光比改善量的影响.模拟计算表明,信号光功率每增加3 dB,λpk,s就需向长波长移动约7 nm.信号光ER增加、参考光功率增加以及SOA注入电流的增加,λpk,s需向短波长移动.消光比改善量随信号光功率和电流的增加而显著增加,随信号ER的增加而降低,但是参考光功率和波长变化时影响不大.

In order to acquire the largest extinction ratio (ER) of the converted signal in the cross gain modulation (XGM) wavelength conversion, the signal wavelength λ pk,s should be longer than the small signal gain peak wavelength of the semiconductor optical amplifier (SOA). The influence of the signal power, the signal ER, the probe power, the probe wavelength and the drive current of the SOA on λ pk,s  and the improvement of the ER is studied in detail by using the multisection model, and considering the nonsymmetry of the gain profile and the shift of the gain peak wavelength along with the carrier density. It is shown by numerical simulation that λ pk,s should shift to the longer wavelength about 7 nm when the signal power has a increment of 3 dB, while λ pk,s should shift to the shorter wavelength when the signal extinction ratio, the probe power and the drive current of the SOA is increased. The improvement of the ER is enlarged remarkably with the increment of the signal power and the SOA drive current, but decreases with the increase of the signal ER. The change of the probe power and the wavelength has little influence on the improvement of the ER.