The thermal expansion of fiber Bragg grating generates chirps

which are enhanced by the stress produced by its aluminum plate

thus realizing a novel wideband tunable fiber grating dispersion compensator.This compensator has two operating modes

tuning the group time dispersion without central wavelength detuning and tuning the central wavelength without dispersion detuning.The group delay dispersion can be tuned from-350 ps/nm to-690 ps/nm with a center wavelength at 1 551.25 nm.On the other hand

the center wavelength can be shifted by 1 nm with a GVD value around-660 ps/nm.