Jean-François Carlin

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We have measured phase modulation in the first chemical beam epitaxy grown InGaAsP/InP barrier, reservoir, and quantum well electron transfer structures. We obtain a negative refractive index change, DELTAn, similar to that found in the InGaAs/InAlAs system. Using new designs to reduce the leakage current in this material system, we obtain a leakage current

Off-axis electron holography has been used to measure the built-in potential profile across an Al0.85In0.15N/AlN/GaN high electron mobility transistor heterostructure. Profile measurements indicated a polarization-induced electric field of 6.9 MV/cm within ...

Polariton lasers are mostly based on planar cavities. Here we focus on an alternative configuration with slab waveguide modes strongly coupled to excitons confined in GaN/AlGaN quantum wells. We study experimentally and theoretically polariton relaxation a ...

In this study, we propose a novel, high-conductivity multi-channel heterostructure based on lattice-matched InAlN/GaN channels with modulation-doping-induced two-dimensional electron gases (2DEGs). To facilitate device processing, the channel period thickn ...

Chemical beam epitaxy (CBE) grown InAsP/InGaAsP edge-emitting laser diodes on GaAs substrates obtained by localised fusion in a nitrogen environment exhibit high quality fused interfaces. A degradation of fused lasers is observed which is attributed to the disordering of quantum wells at fusion temperatures induced by point defects incorporated during low temperature growth.

III-nitride based microcavities (MCs) appear as one of the most promising candidates for the realization of room temperature (RT) polariton laser diodes. The present work focuses on the properties of low In content InGaN/GaN multiple quantum wells (MQWs) in terms of inhomogeneous broadening, exciton localization energy, and plastic strain relaxation. For a small number of such QWs, an inhomogeneous line broadening of 41 meV is reported, which is compatible with strong coupling regime requirements. By contra

Large errors may occur in the X-ray diffraction determination of epitaxial layer mismatch, thicknesses or/and periodicity if the substrate miscut angle is not taken into account. Misoriented sample rocking curves are indeed strongly affected when the azimuth angle is changed, even in the case of a nearly symmetric reflection. This effect is investigated by directly mapping the reciprocal structure of a GaAs/AlAs multilayer grown on a 4-degrees misoriented GaAs substrate. The measurements, performed using a

We investigate Al2O3- and ZrO2/InAlN/GaN metal-oxide-semiconductor heterostructures (MOS-H) using capacitance-time transients in the temperature range of 25-300 degrees C. A deep-level transient spectroscopy based analysis revealed the maximum interface st ...

We report on the realization of InGaAs-lnGaAsP separate confinement heterostructure multiple quantum well lasers grown by chemical beam epitaxy. We discuss key growth parameters and characterization by secondary-ion mass spectroscopy, transmission electron microscopy, electron-beam-induced current, and x-ray diffraction. Threshold current densities as low as 450 A/cm(2) are obtained on lasers with five strained InGaAs quantum wells, along with internal quantum efficiencies of 90% and optical losses of 5 cm(

We report on InAlN underlayer (UL) to improve the efficiency of near ultraviolet (NUV) light emitting diodes (LEDs). While InGaN UL is commonly used in high-efficiency blue LEDs it may absorb light for shorter wavelengths. InAlN lattice-matched to GaN exhi ...

High-efficiency top-emitting InGaAs/AlGaAs microcavity light-emitting diodes (MCLEDs) have been optimized and fabricated. The structures were grown using molecular beam epitaxy on GaAs substrates. They consist of a three-period Be-doped distributed Bragg reflector (DBR) centred at 950 nm wavelength, a cavity containing three InGaAs quantum wells and a 15-period Si-doped DBR. Different values for the wavelength detuning between the spontaneous emission line and Fabry-Perot cavity mode were explored, between

Microcavity light emitting diodes (MCLEDs) present several interesting features compared to conventional LEDs such as narrow linewidth, improved directionality and high efficiency. We report here on MCLEDs with a top emitting geometry. The MCLED layers were grown using molecular beam epitaxy on GaAs substrates. They consist of a 3-period Be-doped distributed Bragg reflector (DBR) centered at 950 nm wavelength, a cavity containing three InGaAs quantum wells and a 15-periods Si-doped DBR. Different values for

Photonic crystal point-defect cavities were fabricated in a GaN free-standing photonic crystal slab. The cavities are based on the popular L3 design, which was optimized using an automated process based on a genetic algorithm, in order to maximize the qual ...

Deep centers in undoped n-GaN grown by Hydride Vapor Phase Epitaxy were characterized by Deep Level Transient Spectroscopy (DLTS), revealing four known levels with activation energies in the range 0.17-0.94 eV. Deeper levels in the bandgap were observed by ...

Highly selective oxidation of an AlInN interlayer buried in a GaN matrix is demonstrated. This technique was successfully applied to form current apertures in III-nitride light-emitting diodes (LEDs). GaN LEDs were grown by metal-organic vapor phase epitax ...

An AlInN/AlGaN microcavity (MC) containing a GaN/Al0.2Ga0.8N multiple quantum well (MQW) structure is investigated through room temperature (RT) photoluminescence and reflectivity experiments. A vacuum Rabi splitting as large as 50 meV at RT is reported fo ...

A report is presented on InGaN/GaN multiple quantum well laser diodes, grown by metal organic vapour phase epitaxy on c-plane sapphire substrates, including an Al0.83In0.17N cladding layer lattice-matched to GaN. Lasing action is demonstrated for gain-guid ...

We report on an annealing-induced "gate sinking" effect in a 2-nm-thin In0.17Al0.83N/AlN barrier high electron mobility transistor with Ir gate. Investigations by transmission electron microscopy linked the effect to an oxygen containing interlayer between ...

Intrinsic and extrinsic pinning and passivation of ...

Crystallographic point defects (PDs) can dramatically decrease the efficiency of optoelectronic semiconductor devices, many of which are based on quantum well (QW) heterostructures. However, spatially resolving individual nonradiative PDs buried in such QW ...

Jean-François Carlin

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Phase Modulation in Ingaasp Barrier, Reservoir, and Quantum-Well Electron-Transfer Structures, Grown by Chemical Beam Epitaxy

Polarization field mapping of Al0.85In0.15N/AlN/GaN heterostructure

Polariton relaxation and polariton nonlinearities in nonresonantly cw-pumped III-nitride slab waveguides

High conductivity InAlN/GaN multi-channel two-dimensional electron gases

Characteristics of InAsP/InGaAsP Edge Emitting Laser Diodes Obtained by Localised Fusion on GaAs Substrates

Investigation of InGaN/GaN quantum wells for polariton laser diodes

X-RAY-DIFFRACTION ANALYSIS OF LOW MISMATCH EPITAXIAL LAYERS GROWN ON MISORIENTED SUBSTRATES

Interface States and Trapping Effects in Al1O3- and ZrO2/InAlN/AlN/GaN Metal-Oxide-Semiconductor Heterostructures

Chemical Beam Epitaxy of 1.55-Mu-M Separate-Confinement Heterostructure Multiple-Quantum-Well Laser-Diodes

InAlN underlaver for near ultraviolet InGaN based light emitting diodes

Design and characterization of top-emitting microcavity light-emitting diodes

High efficiency top-emitting microcavity light-emitting diodes

Gallium nitride L3 photonic crystal cavities with an average quality factor of 16 900 in the near infrared

Characterization of deep levels in n-GaN by combined capacitance transient techniques

Selective oxidation of AlInN layers for current confinement in III-nitride devices

Large vacuum Rabi splitting in a multiple quantum well GaN-based microcavity in the strong-coupling regime

Blue laser diodes including lattice-matched Al0.83In0.17N bottom cladding layer

Metal-related gate sinking due to interfacial oxygen layer in Ir/InAlN high electron mobility transistors

Interplay of intrinsic and extrinsic states in pinning and passivation of m-plane facets of GaN n-p-n junctions

Imaging Nonradiative Point Defects Buried in Quantum Wells Using Cathodoluminescence