Jean-François Carlin

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Electrical-transport properties of mesoscopic junctions consisting of a ballistic two-dimensional electron gas coupled at two sides to overlaying superconducting contacts are presented, The properties suggest that, despite the presence of transport limiting barriers in the sample, supercurrents are carried by a few modes that have near-unity transmission probability. We can qualitatively account for the presence of these resonances by the theory of disorder-induced opening of tunnel channels.

We report on time-resolved photoluminescence measurements carried out along the thickness gradient of two types of GaN/AlGaN quantum wells with low Al content in the barriers (5% and 9%, respectively). A reduction of the biexciton binding energy with incre ...

We report on the low-temperature growth of heavily Si-doped (>10(20) cm(-3)) n(+)-type GaN by N-rich ammonia molecular beam epitaxy (MBE) with very low bulk resistivity (

We report the fabrication and characterization of lateral metal-semiconductor-metal (MSM) photodiodes on an InP substrate. The photoabsorbing layer is made of InGaAs covered by a thin InP Schottky barrier enhancement layer. Schottky contacts for the detectors were formed by the evaporation of Au and patterned using a lift-off technique. The MSM photodiodes exhibit a dark current lower than 200 nA at 15-V bias, an efficient photoresponse up to 1.6 mum, and a fast deconvoluted full width at half maximum respo

Very narrow spontaneous emission (Deltalambda similar to 0.5 nm), corresponding to a quality factor Q in excess of 800, has been obtained under continuous-wave excitation at room temperature with an AlInN/GaN monolithic microcavity. The structure is made o ...

We present a study on the improvement of the external Quantum Efficiency (QE) of Gallium-Nitride-based Light Emitting Diodes (LEDs) by the use of the Single Mirror (SMLED) design [N.E.J. Hunt et al., Electron. Lett. 28, 2169 (1992)]. Three different substrate emitting LEDs are compared by measurements and simulations. An increase in the external QE by more than a factor of two is demonstrated, due to the enhancement of the Light Extraction Efficiency for the SMLED design. Using the SMLED design leads to val

The insertion of an InGaN underlayer (UL) is known to strongly improve the performance of InGaN/GaN quantum well (QW) based blue light emitting diodes (LEDs). However, the actual physical mechanism responsible for it is still unclear. We thus conduct a sys ...

The production cross section of a top quark pair in association with a photon is measured in proton-proton collisions in the decay channel with two oppositely charged leptons (e(+/-)mu(-/+), e(+)e(-), or mu(+)mu(-)). The measurement is performed using 138 ...

We report on the progress in the growth of highly reflective AlInN-GaN distributed Bragg reflectors deposited by metalorganic vapor phase epitaxy. Al1-xInxN layers with an In content around x similar to 0.17 are lattice-matched to GaN, thus avoiding strain ...

We report a novel three-contact vertical-cavity surface-emitting laser (VCSEL) for use in polarization-sensitive optical applications. The device consists of two vertical cavities, coupled by a common mirror. We demonstrate that one can independently choose both the power of the output beam-through the current in the first cavity-and the polarization state-through the bias applied to the second cavity. The control of the polarization state is performed with a control voltage in the range -2 to 0 V. Within t

Nonintentionally doped 200-nm-thick In0.16Al0.84N/n(+)-GaN samples were grown by metal-organic vapor phase epitaxy and used for the electrical characterization of InAlN. In the temperature range 180-400 K, the forward current of Schottky diodes is dominate ...

Making use of bound states in the continuum, we present experimental results on efficient second harmonic generation in photonic crystal cavities supporting doubly-resonant modes. The second harmonic emission is a vortex beam with radial polarization and e ...

The pressure-induced changes in the electronic band structures of In-containing nitride alloys, InxGa1-xN and InxAl1-xN are examined experimentally as well as by ab initio calculations. It is found that the band gap pressure coefficients, dE(g)/dp, exhibit ...

The authors report on the ability to control the polarity of sputter deposited AlN001 thin ﬁlms using seed layers. Reactive sputter deposition leads to N-polarity on any substrate hitherto applied, i.e., Si111, sapphire, SiO2, and polycrystalline metals su ...

We report a study of self-assembled GaN/AlN quantum dots (QDs) grown by metalorganic vapor phase epitaxy. We have investigated the impact of the AlN template quality on the nucleation of QDs obtained by the so-called Stranski-Krastanov growth mode transiti ...

Al2O3 thin films were deposited by a metal organic chemical vapour deposition on InAIN/GaN heterostructures using Ar or NH3 as a carrier gas. Effects of NH3 and Ar carrier gases on the electrical and structural properties of Al2O3/InAIN/GaN HEMT devices we ...

We propose to use lattice-matched AlInN/GaN to replace the Al(Ga)N/GaN material system for III-nitride Bragg reflectors, despite the poor material quality of AlInN reported until very recently. We report an improvement of AlInN material that allowed for su ...

We demonstrate a standard-free method to retrieve compositional information in AlxIn1-xN thin films by measuring the bulk plasmon energy (E-p), employing electron energy loss spectroscopy (EELS) in a scanning transmission electron microscope (STEM). Two se ...

In this paper, we present an improved version of microcavity light-emitting diodes, relying on the use of a low-index material, aluminum oxide. Our work addresses in particular the injection scheme required by the insulating nature of this oxide. The device we fabricated demonstrated efficiencies up to 28% in air, using only planar technology. In these structures, most of the emission is guided. We further propose to include photonic crystals to extract this guided light. The design of the photonic crystals

A Hall mobility as high as 176,200 cm2V-1s-1 at 77 K with N(d)-N(a) = 1.3 x 10(14) cm-3 has been obtained by adjusting the substrate and the phosphine cracker temperatures. The 2 K photoluminescence spectra show finely resolved excitonic transitions for layers grown above 535-degrees-C with linewidths of 0.07 meV. Excitonic transitions have been recorded between 2 and 250 K. The free exciton energy position leads to a highly accurate expression of the band gap energy, which extrapolates to E(g) = 1.347 eV a

Jean-François Carlin

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Experimental indication for supercurrents carried by opened transport channels

Impact of quantum confinement and quantum confined Stark effect on biexciton binding energy in GaN/AlGaN quantum wells

n(+)-GaN grown by ammonia molecular beam epitaxy: Application to regrown contacts

HIGH-SPEED INP/GAINAS METAL-SEMICONDUCTOR-METAL PHOTODETECTORS GROWN BY CHEMICAL BEAM EPITAXY

Lattice-matched distributed Bragg reflectors for nitride-based vertical cavity surface emitting lasers

GaN-based Single Mirror Light Emitting Diodes with high external quantum efficiency

Burying non-radiative defects in InGaN underlayer to increase InGaN/GaN quantum well efficiency

Measurement of the inclusive and differential t(t)over-bar gamma cross sections in the dilepton channel and effective field theory interpretation in proton-proton collisions at root s=13 TeV

Progress in AlInN-GaN Bragg reflectors: Application to a microcavity light emitting diode

Control of polarization switching in vertical coupled-cavities surface emitting lasers

Shallow donor and deep DX-like center in InAlN layers nearly lattice-matched to GaN

Efficient second harmonic generation in a doubly resonant photonic crystal cavity based on a bound state in the continuum

Anomalous composition dependence of the band gap pressure coefficients in In-containing nitride semiconductors

Sputtering of (001)AlN thin films: Control of polarity by a seed layer

Strain relaxation of AlN epilayers Stranski-Krastanov GaN/AlN quantum dots grown by organic vapor phase epitaxy

InAIN/GaN metal-oxide-semiconductor high electron mobility transistor with Al2O3 insulating films grown by metal organic chemical vapor deposition using Ar and NH3 carrier gases

Progresses in III-nitride distributed Bragg reflectors and microcavities using AlInN/GaN materials

Standard-free composition measurements of AlxIn1-xN by low-loss electron energy loss spectroscopy

Toward ultrahigh-efficiency aluminum oxide microcavity light- emitting diodes: Guided mode extraction by photonic crystals

HIGH-PURITY INP GROWN BY CHEMICAL BEAM EPITAXY