InAs quantum dots on AlGaInAs emitting in the optical C-band at 1.55 µm

We present the formation of InAs quantum dots with a low density on AlGaInAs surfaces lattice-matched to InP(001)-substrates using solid source molecular beam epitaxy. By using very low growth rates and an InAs coverage of 2 to 2.6 monolayers the formation of quantum dots is favoured compared to the formation of quantum dashes. The emission wavelength of the single quantum dots could be varied in the range from 1.10 mum up to 1.55 mum, by adjusting the Aluminium to Gallium ratio in the barrier material. Very low densities of around one dot per mum² were achieved. These quantum dots are therefore promising candidates for single photon generation in the optical C-band (1535 nm - 1560 nm).