Columnar quantum dashes for an active region in polarization independent semiconductor optical amplifiers at 1.55 mu m

Here comes a report on the optical properties of InP based InAs columnar quantum dashes, which are proposed as an alternative for columnar quantum dots in semiconductor optical amplifiers construction since they offer convenient spectral tuning over 1.55 mu m together with a very broad and high gain. Electronic structure details are investigated by photoreflectance and photoluminescence and analyzed by comparison with effective mass calculations. Columnar quantum dash emission from the cleaved edge is examined by polarization resolved photoluminescence showing a transition of the dominant polarization from transverse electric to transverse magnetic with an increase in the quantum dash vertical dimension. (C) 2008 American Institute of Physics. [DOI: 10.1063/1.3009557]