Wong, Y.-J.Y.-J.WongChen, H.-H.H.-H.ChenLai, C.-W.C.-W.LaiYEAN-WOEI KIANGCHIH-CHUNG YANG2018-09-102018-09-10200000304018http://www.scopus.com/inward/record.url?eid=2-s2.0-0033714644&partnerID=MN8TOARShttp://scholars.lib.ntu.edu.tw/handle/123456789/289101https://www.scopus.com/inward/record.uri?eid=2-s2.0-0033714644&doi=10.1016%2fS0030-4018%2800%2900713-6&partnerID=40&md5=48975a5aad7c64dc3e0751d76514b919We report the observed self-modulation phenomena in an external-cavity semiconductor laser, in which a slant ridge-loading waveguide was formed for the gain medium. A region beside the ridge at a cleaved end of the waveguide served as a saturable absorber for self-modulation. Under different conditions of injection current and cavity alignment, we observed three laser operation regimes, including pure cw oscillation, constant-amplitude pulse-like signal on the top of a cw component, and amplitude-modulated pulse-like signal coexistent with a cw component. The amplitude modulation phenomenon is different from the previously reported concurrence of mode-locking and self-pulsation. A model was proposed to explain the observed results.Laser resonators; Mathematical models; Optical communication; Optical waveguides; Oscillations; Pulse amplitude modulation; Q switching; Solid state lasers; Gain switching; Pulsed signal generation; Saturable absorber; Semiconductor lasersjournal article10.1016/S0030-4018(00)00713-62-s2.0-0033714644