A5102242494- GaN-based semiconductor devices and materials
- Semiconductor materials and devices
- Metal and Thin Film Mechanics
- Ga2O3 and related materials
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Advancements in Semiconductor Devices and Circuit Design
- Photocathodes and Microchannel Plates
- Advanced Algebra and Geometry
- Mathematics and Applications
- History and Theory of Mathematics
- Advanced Combinatorial Mathematics
- Advanced Theoretical and Applied Studies in Material Sciences and Geometry
- Retinal Development and Disorders
- History and Developments in Astronomy
- Science, Research, and Medicine
- Microtubule and mitosis dynamics
- Mineralogy and Gemology Studies
- Nonlinear Partial Differential Equations
- Biotechnology and Related Fields
- Algebraic structures and combinatorial models
- Semiconductor Quantum Structures and Devices
- Numerical methods in inverse problems
- Cellular transport and secretion
- Geometric Analysis and Curvature Flows
University College Cork
2001-2023
Stanford University
1986-2016
Aluminium Gallium Nitride ((Al,Ga)N) presents an ideal platform for designing ultra-violet (UV) light emitters across the entire UV spectral range. However, in deep-UV range (<280 nm) these exhibit very low quantum efficiencies, which part is linked to polarization characteristics of (Al,Ga)N wells (QWs). In this study we provide insight into degree optical QW systems operating UV-C by means atomistic, multi-band electronic structure model. Our model not only captures difference valence band...
Light emitters based on the semiconductor alloy aluminum gallium nitride [(Al,Ga)N] have gained significant attention in recent years due to their potential for a wide range of applications ultraviolet (UV) spectral window. However, current state-of-the-art (Al,Ga)N light exhibit very low internal quantum efficiencies (IQEs). Therefore, understanding fundamental electronic and optical properties (Al,Ga)N-based wells is key improving IQE. Here, we target c-plane AlxGa1-xN/AlN by means an...
Aluminum gallium nitride [(Al,Ga)N] has gained significant attention in recent years due to its potential for highly efficient light emitters operating the deep ultra-violet (UV) range (&lt;280 nm). However, given that current devices exhibit extremely low efficiencies, understanding fundamental properties of (Al,Ga)N-based systems is key importance. Here, using a multi-scale simulation framework, we study impact alloy disorder on carrier transport, radiative and non-radiative...
Abstract Non-radiative Auger-Meitner recombination processes in III-nitride based optoelectronic devices operating the visible spectral range have received significant attention recent years as they can present a major contribution to efficiency drop at high temperatures and carrier densities. However, insight into these is sparse for III-N ultraviolet wavelength window. In this work we target temperature dependence of rate (Al,Ga)N/AlN quantum wells by means an atomistic electronic...
It is proved that if H(u) non-decreasing and H (-\infty) \neq (+\infty) , then u (x) describes a graph over disk BR (0), with (upward oriented) mean curvature H(u), there bound on the gradient | Du(0) depends only R, particular function (u). As consequence form of Harnack's inequality obtained, in which no positivity hypothesis appears. The results are qualitatively best possible, senses a) they false constant, b) dependences indicated essential. demonstrations based an existence theorem for...
We present a theoretical study on the impact of alloy disorder carrier transport and recombination rates in an (Al,Ga)N single quantum well based LED operating deep UV spectral range. Our calculations indicate that fluctuations enable 'percolative pathways' which can result improved injection into well, but may also increase leakage from well. Additionally, we find induces localization effects, feature particularly noticeable for holes. These effects lead to locally increased densities when...
Aluminium gallium nitride is a system of interest for developing ultraviolet (UV) optoelectronic devices. Here Urbach tails induced by carrier localization effects play key role in determining device behaviour. We study the electronic structure Al <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</inf> Ga xmlns:xlink="http://www.w3.org/1999/xlink">1−x</inf> N/Al xmlns:xlink="http://www.w3.org/1999/xlink">y</inf>...