Publications associées à Effects of quantum-well indium content on deep defects and reliability of InGaN/GaN light-emitting diodes with under layer

Study of growth-induced point defects and their impact on InGaN-based optoelectronic devices

GaN exhibits a decomposition tendency for temperatures far below its melting point and common growth temperatures used in metal-organic vapour phase epitaxy (MOVPE).This characteristic is known to be a major obstacle for realising GaN bulk substrate. There ...

EPFL2024

III-N blue-emitting epi-structures with high densities of dislocations: Fundamental mechanisms for efficiency improvement and applications

Pierre Christophe Lottigier

Since the dawn of humanity, human beings seeked to light their surroundings for their well-being, security and development. The efficiency of ancient lighting devices, e.g. oil lamps or candles, was in the order of 0.03-0.04% and jumped to 0.4-0.6% with th ...

EPFL2024

Polarization-enhanced GaN Schottky barrier diodes: Ultra-thin InGaN for high breakdown voltage and low Ron

Elison de Nazareth Matioli, Alessandro Floriduz, Zheng Hao

In this work, we present a concept that leverages the strong piezoelectric polarization field in InGaN, which counteracts the external electric field at reverse bias. We show that despite the smaller InGaN band-gap and lower critical electric field, its st ...

2024

Investigation of room-temperature single-photon emitters in GaN-based materials and GaN/AlN quantum dots

Johann Nicolaï Stachurski

Over the past decade, quantum photonics platforms aiming at harnessing the fundamental properties of single particles, such as quantum superposition and quantum entanglement, have flourished. In this context, single-photon emitters capable of operating at ...

EPFL2024

The nanoscale impact of individual nonradiative point defects on InGaN/GaN quantum wells

Thomas Fjord Kjaersgaard Weatherley

Today's world depends on optoelectronic devices: light-emitting diodes illuminate our houses and backlight the displays on our gadgets, while laser diodes underpin fibre-optic communication. Such optoelectronic devices rely on crystalline semiconductor het ...

EPFL2023

GeSn as next-generation material for short-wave infrared single-photon detection

Andrea Giunto

In recent years, the automotive industry has aspired to bring self-driving vehicles to the general public and light detection and ranging (LiDAR) sensors have emerged as the preferred solution for car vision systems. At present, LiDAR technologies employ e ...

EPFL2023

Electrical spectroscopy of defect states and their hybridization in monolayer MoS2

Andras Kis, Oleg Yazyev, Yanfei Zhao, Juan Francisco Gonzalez Marin, Ahmet Avsar, Cheol Yeon Cheon, Kristians Cernevics, Zhenyu Wang, Mukesh Kumar Tripathi, Hyungoo Ji

Defects in solids are unavoidable and can create complex electronic states that can significantly influence the electrical and optical properties of semiconductors. With the rapid progress in the integration of 2D semiconductors in practical devices, it is ...

Nature Research2023

Interface connection of functionalized carbon nanotubes for efficient and stable perovskite solar cells

Mohammad Khaja Nazeeruddin, Ruiyuan Hu, Jianxing Xia

The ionic defects of hetero-junction interfaces always attract and trap carriers via surface electrostatic forces, which are crucial for the efficiency and intrinsic stability of perovskite solar cells (PSCs). Herein, functionalized carbon nanotubes (CNTs) ...

Royal Society of Chemistry2023

Drift-Diffusion Simulations of Charge Transport and Trap Dynamics in Organic Semiconductor Materials

Camilla Arietta Vael-Garn

Polymeric semiconductors have gained significant attention in the field of organic electronics due to their unique properties and potential applications. Through their ability to transport charge carriers and to absorb or emit light, they have attracted mu ...

EPFL2023

From defect to effect: controlling electronic transport in chevron graphene nanoribbons

Oleg Yazyev, Kristians Cernevics

While bottom-up synthesis allows for precise control over the properties of graphene nanoribbons (GNRs), the use of certain precursor molecules can result in edge defects, such as missing benzene rings that resemble a 'bite'. We investigate the adverse eff ...

IOP Publishing Ltd2023

Zn3P2 as an earth-abundant photovoltaic material: from growth to device

Rajrupa Paul

The development of cost-effective and earth-abundant semiconducting materials is imperative for the sustainable deployment of photovoltaic technology. Zinc phosphide (Zn3P2) is a promising candidate for terawatt-scale electricity generation. It has a near- ...

EPFL2023

Single-frequency violet and blue laser emission from AlGaInN photonic integrated circuit chips

Tobias Kippenberg, Anat Siddharth

Chip-based, single-frequency and low phase-noise integrated photonic laser diodes emitting in the violet (412 nm) and blue (461 nm) regime are demonstrated. The GaN-based edge-emitting laser diodes were coupled to high-quality on-chip micro-resonators for ...

Optica Publishing Group2023

Indoor Self-Powered Perovskite Optoelectronics with Ultraflexible Monochromatic Light Source

Felix Thomas Eickemeyer, Tommaso Marcato, Hiroaki Jinno, Lukas Pfeifer

Self-powered skin optoelectronics fabricated on ultrathin polymer films is emerging as one of the most promising components for the next-generation Internet of Things (IoT) technology. However, a longstanding challenge is the device underperformance owing ...

Wiley-V C H Verlag Gmbh2023

Voltage-driven Chemical Reactions Enable the Synthesis of Tunable Liquid Ga – Metal Nanoparticles

Raffaella Buonsanti, Anna Loiudice, Pascal Alexander Schouwink, Valery Okatenko, Coline Marie Agathe Boulanger, Alexander Nicolas Chen, Krishna Kumar

Nanosized particles of liquid metals are emerging materials which hold promise for applications spanning from microelectronics to catalysis. Yet, the knowledge of their chemical reactivity is largely unknown. Here, we study the reactivity of liquid Ga and ...

2023

Scalable Approaches to III-V Nanowires for Photodetection

Nicholas Paul Morgan

III-V semiconductor nanowires have unique properties that make them ideal for advanced photodetectors on inexpensive substrates. For example, they exhibit enhanced or polarization-dependent light absorption, they can form complex heterostructures, and thei ...

EPFL2023

Mechanistic study on the evolution of vacancies in graphene by oxidation by scanning tunneling microscopy

Shaoxian Li

Nanostructured graphitic materials, including graphene hosting Å to nanometer-sized pores, have attracted attention for various applications such as separations, sensors, and energy storage. Graphene with Å-scale pores is a promising next-generation materi ...

EPFL2023

Voltage-driven Reactivity of Liquid Ga and CuGa Nanoparticles for Electrocatalytic CO2 Reduction and Synthesis

Valery Okatenko

The rising atmospheric level of carbon dioxide, CO2, contributes to climate change and poses urgent need to find scalable solutions both to decrease its emissions and to be able to recycle it, if the goals of Paris Agreement to limit the temperature rise a ...

EPFL2023

Polariton lasing in AlGaN microring with GaN/AlGaN quantum wells

Jean-François Carlin, Nicolas Grandjean, Raphaël Butté

Microcavity polaritons are strongly interacting hybrid light-matter quasiparticles, which are promising for the development of novel light sources and active photonic devices. Here, we report polariton lasing in the UV spectral range in microring resonator ...

AIP Publishing2023

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

Jean-François Carlin, Nicolas Grandjean, Camille Haller

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. ...

SPIE-INT SOC OPTICAL ENGINEERING2022

Modeling the electrical characteristic of InGaN/GaN blue-violet LED structure under electrical stress

Jean-François Carlin, Nicolas Grandjean, Camille Haller

The role of deep defects and their physical origin in InGaN/GaN LED are still widely investigated and debated, in particular their impact on the electrical and optical characteristics and on the reliability of the device. In this paper we evaluate the elec ...

PERGAMON-ELSEVIER SCIENCE LTD2022