High-Density GaAs/AlAs Quantum Wires Grown on (775)B-Oriented GaAs Substrates by Molecular Beam Epitaxy

Abstract

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 8×10 5 QWRs/cm. A photoluminescence peak at λ=715 nm from the QWRs with a cross section of about 12×3 nm 2 showed a polarization degree of ( I ∥ - I ⊥ ) / ( I ∥ + I ⊥ ) = 0.11 and a very small full width at half maximum of 15 meV at 4.2 K.