SEMICONDUCTOR LASER DEVICE AND OPTICAL DISK APPARATUS USING THE SAME

摘要

A semiconductor laser device of the present invention includes a substrate (201) made of n-type GaAs, an active layer (204), and a pair of cladding layers sandwiching the active layer (204). The device further includes a spacer layer (205) adjacent to the active layer (204) and a highly doped saturable absorbing layer (206). The carrier life time is shortened by doping the saturable absorbing layer (206) in a high concentration, whereby stable self-sustained pulsation can be obtained. As a result, a semiconductor laser device can be obtained, which has a low relative noise intensity in a wide range of temperatures.