Hi Abu bakar,
dispersion is a parameter of the medium of propagation not for the propagating light.
second order dispersion (or GVD), third order dispersion (TOD) or even higher order dispersions are for the optical fiber not for the soliton.
TOD is the frequency dependence on the GVD. The dispersion properties are specified in units of fs3.
all dispersion parameters are frequency dependant and also depend on the fiber compositions.
in this link you can find values of GVD and TOD for different materials composition at different wavelength.
https://www.newport.com/n/the-effect-of-dispersion-on-ultrashort-pulses
Hope that helps you.
Regards,
Mohamed Abouseif
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