Controlling fiber Bragg grating spectra with in-fiber diode laser light

The spectral responses of metal-coated fiber Bragg gratings controlled by in-fiber diode laser light were first demonstrated. In-fiber diode laser light at 910 nm was leaked out from the fiber and absorbed by the surrounding metallic coating to raise the temperature and change the background refractive index distribution of the gratings. The wide tunability of the resonance wavelength and spectrum width was demonstrated in both uniform and linear chirped gratings.