Crystal orientation effect on intersubband transition properties of (11n)-oriented ZnCdTe/ZnTe semiconductor quantum dots

Crystal orientation effects on intersubband transition properties of (11n)-oriented ZnCdTe/ZnTe quantum dots (QDs) were investigated by using the continuum elasticity and effective mass theories. In a range of the crystal angle below 30°, the subband energy difference is nearly independent of the crystal angle. On the other hand, it gradually increases with crystal angle θ when the angle exceeds 30° and becomes a maximum near the angle (θ=55°) corresponding to a (111) crystal orientation due to the piezoelectric field effect. The transition matrix element becomes a maximum near the angle θ=15° and a minimum near the crystal angle θ=60°.