Study on a novel linear-cavity erbium-doped fiber laser using a 3 dB coupler as the reflecting mirror

A novel linear-cavity erbium-doped fiber laser is proposed and demonstrated. By using a 3 dB coupler as the reflecting mirror and an uniform fiber Bragg grating as the partial reflecting mirror and the wavelength selector, a stable laser output is obtained at room temperature. The full-width at half maximum, the side mode suppression ratio and the output power fluctuation are measured to be small than 0.014 nm, better than 40 dB and less than 0.43 dB, respectively. Furthermore, the lasing wavelength doses not drift in four hours.