Wavelength-switchable erbium-doped fiber ring laser using spectral polarization-dependent loss element

We propose a wavelength-switchable erbium-doped fiber ring laser that uses a spectral polarization-dependent loss element. The element was fabricated by inscribing a long-period grating on a polarization-maintaining fiber. Dual-wavelength switching operation was accomplished by rotating the polarization plane of the fiber laser cavity. The amplitude variation of both laser lines was measured to be less than 1 dB and the signal-to-amplified spontaneous emission ratio was more than ~40 dB.