Tailoring broadband gain incorporating quantum dot fluctuations for a GaInNAs semiconductor optical amplifier

Abstract

It has been observed experimentally that the band edge photoluminescence (PL) of GaxIn1‐xNyAs1‐yquantum well (QW) materials is broadened due to compositional fluctuations with N distribution. These fluctuations can be modelled as quantum dot‐like region at the conduction band minimum in as‐grown GaInNAs/GaAs QWs. We have developed a rate‐equation approach to describe the distribution of electrons in the QW and QD‐like fluctuations which include the carrier recombination from both the conventional 2D QW layer and the inhomogeneous dot‐like fluctuations. The electron dynamics in the QW and QDs states are examined and the resulting carrier population and broadband gain is derived for a single QW. This is then applied to the design of a broadband gain multi‐QW semiconductor optical amplifier (SOA). (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)