Patent ID: 8749879
Filing Date: 2014-06-10
Classification: B82Y,H01S

Abstract:
1. A semiconductor optical amplifier comprising: a semiconductor substrate; a lower cladding layer formed on the semiconductor substrate; a light absorption layer and an optical amplification layer formed on the lower cladding layer; an upper cladding layer formed on the light absorption layer and the optical amplification layer; a common electrode formed on the bottom surface of the semiconductor substrate; an optical amplification layer electrode formed in an optical amplification region where the optical amplification layer is formed, through the upper cladding layer; and a light absorption layer electrode formed in a light absorption region where the light absorption layer is formed, through the upper cladding layer; wherein a band gap of a semiconductor material that forms the light absorption layer is wider than a band gap of a semiconductor material that forms the optical amplification layer, the difference between the band gap of the semiconductor material that forms the light absorption layer and the band gap of the semiconductor material that forms the optical amplification layer is 0.12 eV or more, and the light absorption layer and the optical amplification layer are connected in the light-propagating direction to form an optical waveguide.