Electric states in laterally and vertically arrayed type-II quantum dots

摘要

Laterally and vertically arrayed GaSb type-II quantum dots (QDs) in GaAs are theoretically studied to clarify how the electronic states of carriers are affected by the QD arrangement. By solving the Schrodinger equation under appropriate periodic boundary conditions, we numerically evaluate the wave functions of the carriers and show that different QD arrangements strongly vary the electron wave function. When the QDs are densely arranged in a plane, the electron wave function is spread laterally. For the closely stacked QDs in a vertical direction, the electron wave function is located at the sides of the QDs. We also show that the change of the electron wave function leads to the increase of the oscillator strength; the maximum value of the oscillator strength for the laterally arrayed QDs is four times larger than that for the single QD, while the vertical QD arrangement increases the oscillator strength by up to 36 times. (C) 2015 The Japan Society of Applied Physics