Temporal characteristics of a high-energy Er/Yb-codoped fibre ring laser

We study the temporal characteristics of a high-energy Er/Yb-codoped fibre ring laser. By using cladding pumping and using a fibre Bragg grating (FBG) as a wavelength selector, laser oscillation with the maximum average output power of 425 mW and the slope efficiency of 19.7% has been obtained. Using a section of unpumped Er/Yb-codoped fibre as a saturable absorber, the device can operate in several different operation modes for different pump powers—such as stable self-Q-switched, self-mode-locked pulse, and continuous-wave (CW) mode-locked operation. As there is no active element inside the cavity, this laser potentially has many advantages over conventional pulsed fibre laser systems.