Exciton states in InGaAsP/InP core-shell quantum dots under an external electric field

The effect of an external electric field on the exciton states of InGaAsP/InP core-shell quantum dots is investigated through the variational method. The effect of the shell thickness, core radius, electric field strength, and material components on the exciton states are analyzed in detail. The numerical results show that the electron and hole energies decrease as the shell thickness or core radius is increased. The Bohr radius is a nonmonotonic function of the shell thickness or core radius, and the change of the exciton binding energy is nonlinear as the shell thickness or core radius is increased. With increasing electric field strength, the Bohr radius increases while the exciton binding energy decreases. The exciton binding energy decreases (increases) as the Ga (As) component is increased.