DIAMAGNETIC SHIFT AND OSCILLATOR STRENGTH OF 2-DIMENSIONAL EXCITONS UNDER A MAGNETIC-FIELD IN IN0.53GA0.47AS INP QUANTUM-WELLS/

We studied magneto-optical absorption spectra of the ground-state elec tron-heavy-hole exciton resonance in In0.53Ga0.47As/InP quantum wells. As the magnetic field perpendicular to the quantum-well layers was in creased, the exciton resonance showed diamagnetic shifts and its integ rated intensity increased. Magneto-optical data were analyzed using ef fective-mass equations which include conduction and valence-subband no nparabolic dispersion and the wave-vector dependent transition-matrix element with the second-order k.p terms. We found that the exciton wav e function for the relative in-plane motion shrinks in real space and expands in k space due to the in-plane parabolic confinement potential by the magnetic fields. This enhanced the integrated intensity and th us, the oscillator strength. We evaluated the exciton reduced effectiv e mass, Luttinger-Kohn valence-band effective-mass parameters, conduct ion-band effective mass, and a momentum matrix element between s- and p-state band-edge basis functions.