(color online) (a) and (b) Orientation of electron (blue) and hole (yellow) wave functions for a lens-shaped QD on two substrates with different orientations.^[50] (c) Atomic force microscope analysis of the sample surface in the work by Kuroda et al.^[54] (d) Scheme of the pyramidal QD structure.^[52] (e) Profile of the pyramidal InGaAs_1−xN_x QDs (the upper figure is the atomic force microscope results, the lower figure shows the SEM result of the sample after removing the substrate).^[53]