Indium Distribution in Ingaas Quantum Wires Observed with the Scanning Tunneling Microscope

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We report evidence of a large blue shift (up to 70 meV) in the photoluminescence spectra of InAs/InP island like quantum wells following the reduction of the InP top barrier layer thickness from 6 nm to near zero. The photoluminescence intensity only starts to decrease when the top barrier thickness falls below 1.5 nm, indicating that radiative recombinations in the islands are very efficient. These results are well understood by a model assuming a vacuum confinement energy close to 5 eV. (C) 1997 American

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When a growth interruption is applied to the top interface of a nominally 3 monolayers (ML) thick InAs quantum well (QW), grown on an InP substrate, the InAs layer relaxes by formation of three-dimensional (3D) islands. The emission from the QW is split into at least 8 peaks. Each peak corresponds to an integral number of MLs of InAs. Using cathodoluminescence imaging and photoluminescence excitation spectroscopy, we demonstrate that the emission originates in 3D islands with a lateral extension of less tha

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We show that dielectric objects much smaller than the wavelength used to illuminate them, can produce a confined electric field that perfectly reproduces their shape. This field can be recorded by a scanning near-field optical microscope (SNOM), which explains how these devices reach a resolution far beyond the diffraction limit.

Indium Distribution in Ingaas Quantum Wires Observed with the Scanning Tunneling Microscope

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Using diffusion-relaxation MRI to estimate the inner radius of co-electrospun axon-mimicking fibres

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Full tungsten and platinum nanoprobes for electrically conducting scanning probe methods

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Confinement of surface state electrons in Fabry-Perot resonators

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