  Quantum fluctuations of optical fiber Bragg grating solitons are investigated
numerically by the back-propagation method. It is found for the first time that
the bandgap effects of the grating act as a nonlinear filter and cause the
soliton to be amplitude squeezed. The squeezing ratio saturates after a certain
grating length and the fundamental Bragg soliton produces the optimal squeezing
ratio.
