PHOTOLUMINESCENCE SPECTROSCOPY OF SELF-ASSEMBLED (INGA)AS QUANTUM DOTS IN HIGH MAGNETIC-FIELDS

Structures are investigated with InAs and In0.5Ga0.5As self-organised quantum dots embedded in GaAs matrices grown on (1 0 0) and (3 1 1) su bstrates. The photoluminescence (PL) line widths for In0.5Ga0.5As quan tum dots on the high-index planes are significantly narrower than have previously been reported. From the diamagnetic shift of the PL in mag netic fields up to 42 T, the spatial extent of the carrier wave functi on is estimated and compared with the geometrical size of the dots. A model is developed to qualitatively explain the narrow PL and large di amagnetic shift for the quantum dots grown on (3 1 1) planes. (C) 1998 Elsevier Science B.V. All rights reserved.