EXTERNAL RESONATOR TYPE SEMICONDUCTOR LASER DEVICE

摘要

PURPOSE:To provide a short pulse generating device which has a high-frequency chirping characteristic with excellent linearity and that allows optical pulse compressing effect by permitting the activating layer of a semiconductor amplifier to have a multi-layer quantum well structure whose film thickness is the absorption length of an exciting light or more or the diffusion length of an injecting carrier or more. CONSTITUTION:An external resonator type semiconductor laser device 11 is provided with a semiconductor amplifying element 12 which has an activating layer 13 and optical pulse compressing mechanisms 6 and 7. The activating layer 13 is permitted to have a multi-layer quantum well structure which allows the film thickness to be the absorption length of exciting light or more or the diffusion length of an injecting carrier or more. For example, the semiconductor amplifying element 12 is provided with the activating layer 13 and a resonator mirror (laser reflecting mirror) 14 and a laser resonator is provided in the thickness direction of the activating layer 13. The element 12 is what is called a plane emitting semiconductor laser which has a vertical resonator structure. The activating layer 13 has a multi-layer quantum well structure which is effective as a structure that suppresses carrier diffusion.