  A fiber Bragg grating (FBG) with an inverse-Gaussian apodization function is
proposed and fabricated. It is shown that such a FBG possesses easily
controllable dual-wavelength narrow transmission peaks. Incorporating such a
FBG filter in a fiber laser with a linear cavity, stable dual-wavelength
emission with 0.146 nm wavelength spacing is obtained. It provides a simple and
low cost approach of achieving the dual-wavelength fiber laser operation.
