Migration enhanced epitaxiall growth of a quantum wire superlattice and a photoluminescence excitation and magnetoluminescence analysis

A GaAs and Al0.5Ga0.5As quantum wire (QWR) has been successfully grown by migration-enhanced epitaxy in a vicinal GaAs substrate. The 15 x 19 ML GaAs QWR with Al0.5Ga0.5As barriers was analyzed by magnetic-field-dependent photoluminescence (PL) and polarization-dependent PL excitation spectroscopy (PLE). The heavy-hole and the light-hole coupled excitons observed at 1.957 and 1.975 eV, respectively, showed a clear difference in PLE intensity response for a 90 degrees polarization change, which is typical in a well-defined QWR. A small diamagnetic shift and a linewidth broadening of the PL peak by magnetic fields up to 20 T were also observed, which present a clear indication of the 1-D lateral confinement of the magnetoexciton.