Band Alignment Transition from Type I to Type II of InP/ In0.48Ga0.52P quantum Dots

Band alignment transition from type-I to type-II of InP/In0.48Ga0.52P quantum dots (QDs) is observed by modifying the geometrical factors of the dome-shaped QDs. Strain distribution in InP/In0.48Ga0.52P QD is calculated using a valence force field (VFF) model. With the strain Hamiltonian from the VFF model, electrical structures of the QDs are obtained using 8-band k•p model. The results from this theoretical study show that the band alignment of the InP/In0.48Ga0.52P QDs can be tailored from type-I to type-II by controlling the size of the QDs, and flat valence band can be achieved at certain values of height and width of the QDs. In addition, InP/In0.48Ga0.52 QDs of various sizes with the same effective bandgap but different band alignment is observed.