Dear Aadil
The phase change or phase mod like SPM or XPM is dependent on many factors like non-linear length,intensity etc.so you may change the degree of SPM or XPM by varying the pump/signal intensity as per your wish.Be clear that as a result of PM,your CW carrier will be modulated and the pulses experience chirp as a result of SPM/XPM
regards
we may have detail discussion over phone as well