Self-matched stretched-pulse additive-pulse mode-locked fiber lasers formed with apodized chirped gratings

Summary form only given. Without critical wavelength-order cavity-length matching, coupled-cavity passively mode-locked fiber lasers using fiber gratings have been proved to give stable mode-locked pulses. According to our previous work, the cavity-length self-matching originated from the wavelength-dependent effective penetration lengths of the gratings. The mismatch of the cavity lengths is compensated by the difference of the effective penetration lengths between the gratings. In this paper, we present a system using apodized chirped fiber gratings to achieve the cavity-length self-matching operation. Furthermore, due to the special dispersion characteristics of apodized chirped gratings, pulses will have stretched-pulse amplification actions in such a laser system.