Optical spectroscopy of a GaAs/AlGaAs quantum wire structure using near-field scanning optical microscopy

Abstract
We report the first spectroscopic study using a low temperature near-field scanning optical microscope. We have studied an array of GaAs/AlGaAs cleaved edge overgrowth quantum wires. The three luminescence peaks originate from different structures in the sample: The (001)-oriented multiple quantum wells, the (110)-oriented single quantum well, and the quantum wires. The linewidth of the quantum wire emission is related to roughness in the (110)-oriented single quantum well. Quenching of the multiple quantum wells and single quantum well emission near the quantum wires is attributed to diffusion of photoexcited carriers into the wires.