RESONANT MAGNETOLUMINESCENCE OF HIGH-QUALITY GAAS

We have observed a new type of magneto-optical resonance in the luminescence of GaAs samples. When exciting 10 meV to 80 meV above the fundamental gap resonant magneto-luminescence has been observed at a few meV below the laser energy. More than 14 lines with widths of less than 0.5 meV have been recorded in both sigma+ and sigma- polarizations starting at fields as low as 0.6 T. From their polarizations and magnetic-field dependence these lines have been attributed to interband transitions between electron and light hole Landau levels with indices from n = 2 to n = 15. The effects of band nonparabolicity as well as resonant polaron interaction have been directly seen in the spectra. The classical limit of large n at low fields is well realized in our experiments. The light hole mass and effective g-factor have been found to be m(lh) = (0.078 +/- 0.002)m0 and g(lh) = 30.7 +/- 0.7 for a magnetic field along the [001] direction.