  We theoretically study the optical properties and the electronic structure of
highly elongated quantum dots (quantum dashes) and show how carrier trapping
due to geometrical fluctuations of the confining potential affects the
excitonic spectrum of the system. We focus on the study of the optical
properties of a single exciton confined in the structure. The dependence of the
absorption and emission intensities on the geometrical properties (depth and
position) of the trapping center of a quantum dash is analyzed and the
dependence of the degree of linear polarization on these geometrical parameters
is studied in detail.
