Jean-Daniel Ganière

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Degradation defects induced by electron-beam bombardment in Zn1-xCdxSe/ZnSe (001) graded-index separate-confinement blue-green laser structures have been characterized by transmission electron microscopy. Most defects appear as tree-like arrangements of small extrinsic and intrinsic dislocation loops opening in +/-[100] or +/-[010] directions and are located within the quantum well or at its boundaries. The Burgers vectors of the loops were identified as b = 1/2[01(1) over bar] and b = 1/2[10(1) over bar] f

We report on time-resolved photoluminescence studies of tunnelling in a system of asymmetric double quantum wells (QWs). We employ a structure with a semimagnetic QW to align carrier spins and with excess concentration of electrons to provide a sensitive tool for studying the heavy hole dynamics. We prove the existence of hole tunnelling and demonstrate an efficient spin transfer in the process. A semi-empirical model describes qualitatively the experimental findings.

We present results obtained both with scanning electron microscopy (SEM) in the cathodoluminescence (CL) mode and transmission electron microscopy (TEM) on ZnCdSe/ZnSe electron-beam-pumped laser structures. This investigation aims at establishing a relationship between different parameters measurable in electron microscopy and the lasing activity of the structures.

The lateral transport of excess carriers in metal organic chemical vapor deposition grown GaAs/AlxGa1-xAs(x=0.5) 20 angstrom thick single quantum well structures is studied by cathodoluminescence (CL) between 5 K less-than-or-equal-to T less-than-or-equal-to 170 K. Impurity and native defect related transitions are found to take place around grown-in dislocations where well thickness variations are also found. The CL intensity of free excitons and/or transitions involving impurities and native defects is me

Spatio-time-resolvedcathodoluminescence (STRCL) spectroscopy isimplemented to assess the local carrier dynamics in a 70 nm-thick, very low threading dislocation (TD) density, pseudomorphic m-plane In GaN epilayer grown on a freestanding GaN substrate by me ...

We present a low-temperature time-resolved cathodoluminescence study on (In,Ga)N/GaN quantum wells grown on the (11-22) facets of non-coalesced ELO-GaN. Taking advantage of the quantum confined Stark effect, such structures have been proposed as promising ...

The structural and optical properties of controlled-heterostructure-potential, low-dimensional GaAs/AlGaAs nanostructures self-formed during organometallic chemical vapor deposition in tetrahedral pyramids etched in (111) B-GaAs substrates, are investigate ...

Improved Si1-xGex/Si hetero-epitaxy has been achieved by RTCVD in the presence of small amounts of C3H8 during growth. Carbon presumably scavenges oxygen and acts as a surfactant to inhibit three dimensional growth.

Characterization of impurety diffusion induced disordering in GaAs/AlGaAs multiquantum well structures, grown by molecular beam epitaxy, has been carried out by scanning electron microscopy.

We report, for the first time, a direct relationship between the composition fluctuation on the ternary layer grown by atmospheric pressure metalorganic vapor-phase epitaxy (AP-MOVPE) and the pulsed character of high-vapor-pressure metalorganic (MO) flows. We show that the grwoth rates of GaAlAs and GaInAs layers, grown with trimethylgallium (TMG) and triethylgallium (TEG) sources, are of tens of angstrom per bubble for the methyl case and a few angstrom for the ethyl one.

The dynamics of excitons and trions in CdTe modulation-doped quantum wells are studied as a function of temperature by three-pulse four-wave mixing experiments. It is shown that trions are localized by interface roughness scattering and/or by the remote ionized donor potential at low temperature in the low-density regime. The diffusivity of excitons and trions increases with temperature but their mobilities are limited by acoustical phonon scattering, The coherence study reveals that the system is inhomogen

Lattice-matched Zn1-yCdySe/InxGa1-xAs heterojunctions can be fabricated by molecular beam epitaxy on GaAs(001) 2x4 surfaces in a wide range of compositions provided that a suitable strain relaxation profile is achieved within the ternary m-V buffer layer. We focus here on the structural properties of the resulting II-VI/III-V heterostructures and discuss the distribution of native defects, including misfit and threading dislocations, stacking faults, and surface corrugations, (C) 1998 American Vacuum Societ

When the carrier density is increased in a semiconductor, according to the predictions of Sir Nevil Mott, a transition should occur from an insulating state consisting of a gas of excitons to a conductive electron-hole plasma. This crossover, usually refer ...

Jean-Daniel Ganière

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Degradation defects in electron-beam-pumped Zn1-xCdxSe/ZnSe graded-index separate-confinement heterostructure (GRINSCH) blue and blue-green lasers

Tunnelling of spin-polarized holes in asymmetric double quantum well structures

Cathodoluminescence and transmission electron microscopy investigation of ZnCdSe/ZnSe electron-beam-pumped laser structures

Lateral Transport in Gaas/Algaas Quantum-Wells

Implementation of spatio-time-resolved cathodoluminescence spectroscopy for studying local carrier dynamics in a low dislocation density m-plane InGaN epilayer grown on a freestanding GaN substrate

Time-resolved cathodoluminescence on polychromatic light emitting (In,Ga)N quantum wells grown on (11-22) GaN facets

Pyramidal GaAs/AlzGa1-zAs quantum wire/dot systems with controlled heterostructure potential

Improvement of Crystal Quality of Epitaxial Silicon-Germanium Alloy Layers by Carbon Additions

Sem Observations of Zinc Diffusion Induced Disordering in Gaas/Algaas Multiquantum Well Structures

Effect of Metal-Organic Composition Fluctuation on the Atmospheric-Pressure Metal-Organic Vapor-Phase Epitaxy Growth of GaAlAs/GaAs and GaInAs/InP Structures

Dynamics of excitons and trions in CdTe quantum wells: Direct observation of diffusion and localization

Native extended defects in Zn1-yGdySe/InxGa1-xAs heterostructures

Biexcitonic molecules survive excitons at the Mott transition

Probing carrier dynamics in nanostructures by picosecond cathodoluminescence

Exciton Localization On Basal Stacking Faults In A-Plane GaN Probed By Picosecond Time-Resolved Cathodoluminescence

Inhomogeneous strain relaxation and detect distribution of ZnTe layers deposited on (110)GaAs by metalorganic vapor phase epitaxy (vol 78, pg 229, 1995)

Time-Resolved Cathodoluminescence of InGaAs/AlGaAs Tetrahedral Pyramidal Quantum structures

Inhomogeneous Strain Relaxation and Defect Distribution of Znte Layers Deposited on (100)Gaas by Metalorganic Vapor-Phase Epitaxy