PHOTOLUMINESCENCE INTENSITY OF INGAAS GAAS STRAINED QUANTUM-WELLS UNDER HIGH MAGNETIC-FIELDS

Photoluminescence measurements have been performed in pulsed high magnetic fields up to 40T and temperature of 4.2K on InXGa1-XAs/GaAs strained quantum wells, grown with several different well widths, 30, 50, 60 and 75Å on the same substrate. The magnetic field is applied in configurations perpendicular and parallel to well planes. Drastic increase of the emission intensity originating from the narrow quantum well is observed only in the parallel field configuration. The increase can be understood as an enhancement of exciton oscillator strength due to the shrinkage of the exciton wave function by the applied high field in the parallel configuration. The agreement between the magnetic length at high fields and the expansion of exciton wave function estimated theoretically support the above interpretation. © 1990.