A theoretical study of the growth-direction magnetic-field effects on the exciton
photoluminescence peak energies in GaAs–Ga1−xAlxAs quantum-dot/ultrathin
quantum-well systems is presented. Calculations are performed within the
effective-mass approximation and taking into account nonparabolicity effects
for both the conduction-band and valence-band effective masses. We use a
simple ‘QD + ultrathin QW’ model heterostructure to mimic the actual physical
system, and calculated results for the exciton diamagnetic shifts are found in
overall agreement with recent experimental measurements. |