Artificial array of InAs quantum dots on a strain-engineered superlattice

Aligned quantum dots (QDs) were successfully formed along the 〈1 1 0〉 direction on a strain-engineered layer using InAs/GaAs superlattice (SL). The aligned QDs have good quantum confinements without degradation of optical properties. It is found from transmission electron spectroscopy and Raman scattering measurements that the strained InAs/GaAs SL acts as a strained layer having tensile stress for the site control of QDs without the generation of defects acting as nonradiative recombination centers. The artificial array of self-assembled QDs can provide a clue for the easy and high throughput fabrication method for the application of single-electron devices.