QUANTUM WIRES PREPARED BY MOLECULAR-BEAM EPITAXY REGROWTH ON PATTERNED ALGAAS BUFFER LAYERS

Modulation doped GaAs quantum wires are prepared by molecular beam epi taxy regrowth on patterned AlGaAs buffer layers. The structural proper ties are investigated by scanning electron microscopy and by transmiss ion electron microscopy. Far-infrared spectroscopy provides informatio n about the lateral confinement and the carrier density in the quantum wires. The measurements indicate a distinct dependence of the electro nic width on the orientation of the quantum wires within the (100) pla ne. Confinement energies of 6.9, 9.3, and 11.7 meV are determined for the [011], [001], and the [011BAR] wire orientations, respectively.