Micro-photoluminescence study at room temperature of sidewall quantum wires formed on patterned GaAs (311)A substrates by molecular beam epitaxy

Lateral quantum wires are grown by molecular beam epitaxy of GaAs/(AlGa)As multilayer structures on patterned GaAs (311)A substrates along the sidewall of 15-20 nm heigh mesa stripes oriented along [01-1]. The wire formation relies on the preferential migration of Ga atoms from the mesa top and bottom toward the sidewall. The quantum wires having a lateral width of similar to 50 nm are characterized by micro-photoluminescence spectroscopy between 8 K and room temperature. In the whole temperature regime the quantum wire exhibits a clear luminescence peak, well separated from the quantum well peak at the mesa top and bottom forming the lateral barriers. IVIicro-photoluminescence linescans reveal the strong spatial confinement of the photogenerated carriers even at room temperature.