Magneto-luminescence of quasi-zero dimensional In0.25Ga0.75As/GaAs quantumdots

We report photoluminescence measurements on In0.25Ga0.75As/GaAs quantum wel l and dots grown on (1 1 1)B GaAs substrate in high magnetic fields up to 4 5 Tesla. A well-defined PL line with full width at half maximum of approxim ately 5.5 meV is observed. From an analysis of the zero field transition en ergy, we point out the importance of an internal piezoelectric field. By an alyzing the diamagnetic shift of the PL in both Faraday and Voigt configura tions, the optical characteristics of a quasi-zero dimensional exciton are discussed. (C) 1998 Elsevier Science B.V. All rights reserved.