Abstract

Progress in fine patterning and growth techniques has made it possible to fabricate quantum wires (QWRs) and quantum dots on the nanometer scale. We have reported the fabrication of GaAs/A1As trench-buried QWRs with nearly rectangular cross-sections and lateral size control on a scale of 20 nm, which is small enough to produce lateral quantum confinement effects. In fact, photoluminescence (PL) properties of these QWRs showed strong PL anisotropy due to their one-dimensional (1-D) band structures. It has been theoretically predicted that the 1-D hole effective mass in the confinement directions depends on the cross sectional shape of the QWR because two-dimensional (2-D) quantum confinement effects modify the valence electronic states, where the heavy-hole and light-hole subbands are strongly coupled.¹ In this paper, we investigate low-temperature (15 K) polarization-dependent photoluminescence excitation (PLE) properties of QWRs with different cross-sectional shapes in order to analyze the dependence of valence-subband structures on the cross-sectional shape of the wire.

© 1995 IEEE