PHOTOLUMINESCENCE AND ELECTROLUMINESCENCE OF HIGH-DENSITY GAAS QUANTUM WIRES ARRAYS

Photoluminescence (PL) and electroluminescence (EL) measurement of GaA s/AlGaAs quantum wires (QWR) located in the active region of a p-i-n j unction are reported. The samples are fabricated by molecular-beam epi taxial growth on V-grooved substrates. Good control of the interface, defect density and doping profile have been achieved. Homogeneous curr ent injection into the quantum wires is achieved with efficiencies com parable to current injection into a quantum well control sample. PL wi th and without an applied voltage across the junction was measured at 86 K and 300 K for different excitation densities. Peaks appearing wit h an applied voltage correspond to the active-region QWR transitions a nd are also observed on the EL spectra measured at 120 K and at 300 K. Clear evidence of 1D confinement is observed in both PL and EL spectr a. They show a one:dimensional splitting of about 24 meV and a saturat ion of the ground state at high excitation density. The polarisation o f the PL and EL is in good agreement with the expected anisotropy of t he 1D matrix elements.