SEMICONDUCTOR OPTICAL AMPLIFIER, SEMICONDUCTOR LASER DEVICE ASSEMBLY, AND METHOD FOR ADJUSTING POSITION OF SEMICONDUCTOR OPTICAL AMPLIFIER

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor optical amplifier comprising a GaN-based compound semiconductor and capable of achieving still higher optical output.SOLUTION: A semiconductor optical amplifier 200 is provided with: (a) a layered structure created by sequentially stacking a first compound semiconductor layer comprising a GaN-based compound semiconductor, a third compound semiconductor layer, and a second compound semiconductor layer; (b) a second electrode 262 formed on the second compound semiconductor layer; (c) a first electrode electrically connected to the first compound semiconductor layer. The layered structure has a ridge stripe structure in which, when Wrepresents the width of the ridge stripe structure in a light emission end face 203 and Wrepresents the width of the ridge stripe structure in a light incident end face 201, W>Wis satisfied. In a region inward of the layered structure from the light emission end face 201 along an axial line AXof the semiconductor optical amplifier is provided with a carrier non-injection region 205. The second electrode 262 is configured from a first portion 262A and a second portion 262B separated by a separation groove 262C. The carrier non-injection region 205 is provided with the second portion 262B of the second electrode.