Switchable quadruple-wavelength Erbium-doped fiber laser based on a chirped fiber grating and polarization-maintaining fiber

A switchable quadruple-wavelength Erbium-doped fiber laser based on two Sagnac loops with a chirped fiber grating and polarization-maintaining fiber is proposed and demonstrated experimentally at room temperature. The two loops act as comb filters to excite multi-wavelength output. On the basis of the polarization hole burning effect, the laser can switch flexibly to output ten different modes from single-wavelength to quadruple-wavelength. All of the lasing lines with narrow linewidth have the optical signal-to-noise ratio of more than 35 dB. The laser with good power uniformity shows better stability with respect to the wavelength and peak power. (C) 2015 Elsevier Ltd. All rights reserved.