SELF OSCILLATION SEMICONDUCTOR LASER SYSTEM

摘要

PROBLEM TO BE SOLVED: To enable stable self oscillation even in high-temperature ranges by sandwiching at least part of both the sides of a second clad layer between low-refractive index current block layers the refractive index of which is lower than that of the clad layer. SOLUTION: Low-refractive index current block layers 114 are so formed that at least part of both the sides of a second clad layer 110 of second conductivity type is sandwiched between them. The refractive index of the low- refractive index current block layers 114 is reduced to a value lower than the refractive index of the second clad layer 110 of the second conductivity type sandwiched between the low-refractive index current block layers 114. This actual refractive index guide structure allows waveguide loss and ridge passage resistance to be reduced and thus threshold current, operating current, and operating voltage can be reduced. As a result, current spreading direct under the low-refractive index current block layers 114 can be reduced. Thus, reduction in amount of saturable absorption due to temperature rise can be reduced and self oscillation can be sustained even at high temperature.