Surface morphology of self-assembled vertically stacked InAs quantum dots by atomic force microscopy

In quantum dots (QDs) three-dimensional confinement of carriers leads to energy level discreteness to exhibit a rich spectrum of phenomena including quantum confinement, exchange splittings, Coulomb blockade, and multiexciton transitions. In this paper, five-period vertically stacked samples with size-controlled growth were grown by molecular-beam epitaxy (MBE) with solid sources, and the surface morphologies of self-assembled vertically stacked InAs quantum dots were characterized by atomic force microscopy (AFM). We described structural and optical properties of vertically aligned InAs QDs embedded in Al0.5Ga0.5As and employed a size-controlled growth procedure for the QDs. The strongly localized electron coupling effect and many-body effect lead to quantum dephase splitting of the ground state energy of the vertically aligned InAs QDs.