Site-controlled InAs/GaAs quantum dots emitting at telecommunication wavelength

We demonstrate site-controlled InAs/GaAs quantum dot (QD) emission at 1.3 mu m telecommunication wavelength. The samples were fabricated by molecular beam epitaxy on patterned substrates, which have been prepared by electron beam lithography and wet chemical etching. By embedding a single layer of positioned QDs in a strain reducing InGaAs quantum well layer, we successfully shifted the emission band beyond the important telecommunication wavelength of 1.3 mu m. Furthermore, the resulting deep carrier confinement allowed us to preserve strong QD luminescence up to room temperature.