In-situ analysis of optoelectronic properties of twin boundaries in AlGaAs by polarized cathodoluminescence spectroscopy in a TEM.
Optoelectronic properties of nanoscale twin boundaries (TBs) in indirect-gap AlGaAs layers were studied by polarized cathodoluminescence spectroscopy in a transmission electron microscope. TBs arranged orderly in a short range, i.e. four or more parallel TBs arranged at regular intervals of nanometre length, emitted an intense monochromatic light polarized parallel to the boundaries. The intensity and the photon energy of the light were examined at different temperatures with different electron fluxes, and the origin of the light was discussed based on a twinning superlattice model. According to the study, it was suggested that the photon energy is tunable by controlling the intervals of TBs, without changing the crystal structure and the composition.
Ohno
Yutaka
Y
Institute for Materials Research, Tohoku University, Aoba-ku, Sendai, Japan. yutakaohno@imr.tohoku.ac.jp