High-density GaAs/AlAs quantum wires grown on (775)B-oriented GaAs substrates by molecular beam epitaxy

GaAs/AlAs quantum wires (QWRs) were found to be naturally formed by a regularly corrugated AlAs/GaAs interface and a flat GaAs/AlAs interface in an AlAs/GaAs/AlAs quantum well with a well width of 3.3 nm grown on a (775)B GaAs substrate by molecular beam epitaxy. The lateral period and vertical amplitude of the AlAs/GaAs interface corrugation were 12 nm and 1.2 nm, respectively. The QWRs were formed side by side with an extremely high density of 8x10(5) QWRs/cm. A photoluminescence peak at lambda = 715 nm from the QWRs with a cross section of about 12x3 nm(2) showed a polarization degree of (I-parallel to - I-perpendicular to)/(I-parallel to + I-perpendicular to) = 0.11 and a very small full width at half maximum of 15 meV at 4.2 K.