Stable narrow line width dual-wavelength communication light source based on a DBR fiber Laser

A dual-wavelength narrow line width laser system, with ultra-narrow wavelength spacing, is proposed and demonstrated. The operation principle of the laser system is based on the pumped-induced thermal effects of the Er-Yb-doped fiber DBR laser. We designed and constructed a common Er-Yb-doped DBR fiber laser with proper parameters. With the pump power of the DBR laser increasing, the Bragg wavelengths and the bandwidths of the two gratings will change unequally. When pumped with 45mW, we obtain a stable dual wavelength lasing with the bandwidth of 0.014nm and the wavelength spacing of 0.055nm.