Metamorphic approach to single quantum dot emission at $1.55μm$ on GaAs substrate

We report on the fabrication and the characterization of InAs quantum dots (QDs) embedded in an indium rich $In0.42Ga0.58As$ metamorphic matrix grown on a GaAs substrate. Growth conditions were chosen so as to minimize the number of threading dislocations and other defects produced during the plastic relaxation. Sharp and bright lines, originating from the emission of a few isolated single quantum dots, were observed in microphotoluminescence around $1.55μm$ at 5 K. They exhibit, in particular, a characteristic exciton/biexciton behavior. These QDs could offer an interesting alternative to other approaches as InAs/InP QDs for the realization of single photon emitters at telecom wavelengths.