Semiconductor optical amplifier

Abstract

It is desirable to provide a semiconductor optical amplifier from which it becomes able to obtain a higher output power. A semiconductor optical amplifier in comprises an active wave guiding layer which comprises a passive core region that is formed of a semiconductor, and active cladding regions that are located at both sides of the passive core region and each of that is comprised of an active layer which is formed of a semiconductor and which has an index of refraction to be lower than that of the passive core region, wherein a light is wave guided with being amplified in the active wave guiding layer. Moreover, it is desirable for the active wave guiding layer to be formed of a compound semiconductor, and to be formed by integrating the passive core region and the active cladding regions to be monolithic on to a substrate that is formed of a compound semiconductor by making use of a process of a butt joint growth.

Dependencies are inferred from the claim text.