Publications by Nicolas Grandjean

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We report on the reliability of GaN-based super-luminescent light emitting diodes (SLEDs) emitting at a wavelength of 405 nm. We show that the Mg doping level in the p-type layers has an impact on both the device electro-optical characteristics and their r ...

A comparison of devices with different source-drain gaps has been performed on AlInN/GaN high electron mobility transistors (HEMTs) grown on SiC. The cut-off frequency is effectively improved through shrinking source drain space and reducing gate parasitic ...

In this study, we investigate the impact of two-dimensional MoS2 coating on the optical properties of surface GaN/AlGaN quantum wells (QWs). A strong enhancement in GaN QW light emission is observed with monolayer-MoS2 coating, yielding luminescence intens ...

Deep defects have a fundamental role in determining the electro-optical characteristics and in the efficiency of InGaN light-emitting diodes (LEDs). However, modeling their effect on the electrical characteristics of the LED is not straightforward. ...

In this work the technology and characterization of nanocrystalline diamond (NCD) films directly grown on InAlN/GaN HEMTs is presented. Optimization of GaN based HEMT process steps including metallization stacks is discussed. A fully processed InAlN/GaN HE ...

Quantum dots (QDs) based on III-nitride semi-conductors are promising for single photon emission at noncryogenic temperatures due to their large exciton binding energies. Here, we demonstrate GaN QD single photon emitters operating at 300 K with g((2)) (0) ...

We study the impact of non-radiative defects on Auger recombination in c-plane InGaN/GaN single quantum wells (SQWs) in the efficiency droop regime using high injection time-resolved photoluminescence. The defect density in the SQW is controlled by tuning ...

The evolution of the polariton condensation threshold (P-thr) under incoherent optical pumping is investigated both theoretically and experimentally over a wide range of temperatures (4-340 K) and exciton-cavity photon detunings (-120-0 meV) in a multiple ...

We present a detailed study of the luminescence at 3.42 eV usually observed in a-plane epitaxial lateral overgrowth (ELO) GaN grown by hydride vapor phase epitaxy on r-plane sapphire. This band is related to radiative recombination of excitons in a commonl ...

The authors report the realization of InGaN/GaN light emitting diodes (LEDs) with an electrical injection design suitable for vertical cavity surface emitting lasers. Controlled oxidation of an AlInN interlayer lattice matched to GaN allows confining the i ...

Thanks to its high refractive index contrast, band gap, and polarization mismatch compared to GaN, In0.17Al0.83N layers lattice-matched to GaN are an attractive solution for applications such as distributed Bragg reflectors, ultraviolet light-emitting diod ...

DC and RF measurements of an emerging AIInN/GaN high electron mobility transistor (HEMT) technology for power performances are reported. High electron transport properties in this structure attributed to the material quality are demonstrated. Indeed, in sp ...

Nitride-based blue laser diode structures with either Al0.83In0.17N/Al0.07Ga0.93N or Al0.87In0.13N bottom claddings have been fabricated and compared to standard structures including solely Al0.07Ga0.93N bottom claddings. Lasing emission at 415 nm is achie ...

We study the carrier-density-dependent recombination dynamics in m-plane InGaN/GaN multiple quantum wells in the presence of n-type background doping by time-resolved photoluminescence. Based on Fermi's golden rule and Saha's equation, we decompose the rad ...

We report the observation of midinfrared intersubband (ISB) absorption in nearly lattice-matched AlInN/GaN multiple-quantum-wells. A clear absorption peak is observed around 3 mu m involving transitions from the conduction band ground state to the first ex ...

We investigate the degradation mechanisms of In0.2Ga0.8N/GaN light emitting diodes through combined experimental analysis and simulations. The devices were submitted to constant current stress at 100 mA. Depending on the measuring current level, two degrad ...

We demonstrate room-temperature continuous-wave operation of 425 nm InGaN-based blue laser diodes including a thin Al0.83In0.17N optical blocking layer. Structures are grown on c-plane GaN freestanding substrates with a lattice-matched AlInN layer position ...

Time-resolved cathodoluminescence at 27 K has been performed on a-plane GaN grown by epitaxial lateral overgrowth. We detail the relaxation and recombination mechanisms of excitons [free or bound to neutral donors, or bound to I1-type basal stacking faults ...

AlInN/GaN unpassivated High Electron Mobility Transistor (HEMT) on Sapphire substrate has yielded a maximum drain current density close to 2 A/mm in steady state. Superior gate length downscaling than AlGaN/GaN devices has been observed owing to the possib ...

An indium-containing layer positioned underneath the InGaN/GaN quantum well (QW) active region is commonly used in high efficiency blue light-emitting diodes. Recent studies proposed that the role of this underlayer is to trap surface defects (SDs), which, ...

Nicolas Grandjean

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GaN-based superluminescent diodes with long lifetime

High-speed and low-noise AlInN/GaN HEMTs on SiC

GaN Surface Passivation by MoS2 Coating

Deep defects in InGaN LEDs: modeling the impact on the electrical characteristics

Diamond overgrown InAlN/GaN HEMT

Toward Bright and Pure Single Photon Emitters at 300 K Based on GaN Quantum Dots on Silicon

Impact of defects on Auger recombination in c-plane InGaN/GaN single quantum well in the efficiency droop regime

Condensation phase diagram of cavity polaritons in GaN-based microcavities: Experiment and theory

Exciton localization on basal stacking faults in a-plane epitaxial lateral overgrown GaN grown by hydride vapor phase epitaxy

Efficient current injection scheme for nitride vertical cavity surface emitting lasers

Intrinsic degradation mechanism of nearly lattice-matched InAlN layers grown on GaN substrates

Small-signal characteristics of AlInN/GaN HEMTs

Al0.83In0.17N lattice-matched to GaN used as an optical blocking layer in GaN-based edge emitting lasers

Carrier-density-dependent recombination dynamics of excitons and electron-hole plasma in m-plane InGaN/GaN quantum wells

Midinfrared intersubband absorption in lattice-matched AlInN/GaN multiple quantum wells

Investigation and modeling of the role of interface defects in the optical degradation of InGaN/GaN LEDs

Emission characteristics of GaN-based blue lasers including a lattice matched Al0.83In0.17N optical blocking layer for improved optical beam quality

Low-temperature time-resolved cathodoluminescence study of exciton dynamics involving basal stacking faults in a-plane GaN

AlInN/GaN a suitable HEMT device for extremely high power high frequency applications

GaN buffer growth temperature and efficiency of InGaN/GaN quantum wells: The critical role of nitrogen vacancies at the GaN surface