OPTICAL AMPLIFIER

摘要

PROBLEM TO BE SOLVED: To control polarization dependence in gain characteristics by a simple configuration precisely. SOLUTION: In a first region R1 where length in a stripe direction is L1, the stripe width of an InGaAsP-based bulk active layer 3 is set to be W1. In a second region R2 where length in a stripe direction is set to be L2, the stripe width of the InGaAsP-based bulk active layer 3 is set to be W2. The amount of strain in the InGaAsP-based bulk active layer 3 is set so that the amount of strain has a stripe width existing between the stripe widths W1 and W2 and does not depend on polarization.