Near-field optical characterization of quantum wells and nanostructures

Summary form only given. Low temperature near-field scanning optical microscopy/spectroscopy has proven useful in characterization of quantum confined semiconductor structures even to the extent of revealing the individual optically active quantum constituents of such a system. Specifically, sharp (<0.07 meV), spectrally distinct emission lines of a GaAs/AlGaAs quantum well can be imaged at a specific spatial location, or as a spectral evolution image as the probe is scanned along a line across the surface, or as a real space image at a specific luminescence wavelengths. Temperature, magnetic field, and line width measurements establish that these luminescence centers arise from excitons localized at interface fluctuations.