Magnetophotoluminescence study of the influence of substrate orientation and growth interruption on the electronic properties of InAs∕GaAs quantum dots

We have used photoluminescence in pulsed (⩽50T) and dc (⩽12T) magnetic fields to investigate the influence of substrate orientation and growth interruption (GI) on the electronic properties of InAs∕GaAs quantum dots, grown by molecular beam epitaxy at 480°C. Dot formation is very efficient on the (100) substrate: electronic confinement is already strong without GI and no significant change in confinement is observed with GI. On the contrary, for the (311)B substrate strong confinement of the charges only occurs after a GI is introduced. When longer GIs are applied the dots become higher.