Low-density InP-based quantum dots emitting around the 1.5 μm telecom wavelength range

The authors report on low-density InAs quantum dots (QDs) grown on AlGaInAs surfaces lattice matched to InP using post-growth annealing by solid-source molecular beam epitaxy. Clearly spatially separated QDs with a dot density of about 5 x 10(8) cm(-2) are obtained by using a special capping technique after the dot formation process. High-resolution micro-photoluminescence performed on optimized QD structures grown on distributed Bragg reflector exhibits single QD emissions around 1.5 mu m with narrow excitonic linewidth below 50 mu eV, which can be used as single photon source in the telecom wavelength range. (C) 2014 AIP Publishing LLC.