Polarization independent-type semiconductor optical amplifier

Abstract

A polarization independent-type semiconductor optical amplifier comprises: a strained bulk active layer having a 20 nm to 90 nm-thick and having a tensile strain of a −0.10% to −0.60% strain amount; clad layers provided, sandwiching the strained bulk active layer; and a resonance suppressing means for suppressing resonance of light due to reflection on a light incident end face and a light exit end face of the strained bulk active layer, incident signal light entering at the light incident end face being amplified and exiting at the light exit end face, and an individual transmission gain of the exit signal light being substantially constant independent of a polarization state of the incident signal light. Whereby drastically increased fiber out saturation powers can be obtained with polarization independence retained.

Dependencies are inferred from the claim text.