Tailoring the photoluminescence polarization anisotropy of a single InAs quantum dash by a post-growth modification of its dielectric environment.

Excitonic emission from single InAs/InGaAlAs/InP quantum dashes has been investigated in terms of controlling the polarization anisotropy by altering the shape of the processed sub-micrometer mesa structures. Photoluminescence has been measured from exemplary single quantum dashes emitting around 1.3 and 1.55 µm and placed inside rectangular mesas of various orientation, asymmetry, and sizes. The detected degree of linear polarization of bright exciton emission ranges from -0.1 to ca. 0.55, compared to 0.25 for dashes in unaltered or isotropic in-plane dielectric surrounding. These results are interpreted by numerical simulations using an emitter coupled with a single optical mode in such a mesa and outgoing in the direction normal to the sample surface. [ABSTRACT FROM AUTHOR]