Fast accurate wavelength switching of an erbium-doped fiber laser with a Fabry-Perot semiconductor filter and fiber Bragg gratings

We propose a simple passive method for achieving fast accurate wavelength s witching in an erbium-doped fiber laser. The method relies on a laser cavit y formed with a Fabry-Perot semiconductor filter (FPSF) and narrow-band fib er Bragg gratings (FBGs), where the FBGs set the wavelength references and the FPSF can be tuned by changing its injection current to select a particu lar wavelength from those set by the FBGs. Because of the nonlinearity in t he FPSF, optical negative feedback can be built up in the laser to suppress relaxation oscillations caused by wavelength switching. With this method, a wavelength switching time of less than 25 mus has been achieved experimen tally. (C) 2000 American Institute of Physics. [S0003-6951(01)03801-3].