Title :

Impact of random alloy fluctuations on the carrier distribution in multi-color (In,Ga)N/GaN quantum well systems

Author(s) :

O'Donovan, Michael [Auteur]
Weierstraß-Institut für Angewandte Analysis und Stochastik = Weierstrass Institute for Applied Analysis and Stochastics [Berlin] [WIAS]
Tyndall National Institute [Cork]
Farrell, Patricio [Auteur]
Weierstraß-Institut für Angewandte Analysis und Stochastik = Weierstrass Institute for Applied Analysis and Stochastics [Berlin] [WIAS]
Moatti, Julien [Auteur]
Vienna University of Technology = Technische Universität Wien [TU Wien]
Reliable numerical approximations of dissipative systems [RAPSODI]
Streckenbach, Timo [Auteur]
Weierstraß-Institut für Angewandte Analysis und Stochastik = Weierstrass Institute for Applied Analysis and Stochastics [Berlin] [WIAS]
Koprucki, Thomas [Auteur]
Weierstraß-Institut für Angewandte Analysis und Stochastik = Weierstrass Institute for Applied Analysis and Stochastics [Berlin] [WIAS]
Schulz, Stefan [Auteur]
Tyndall National Institute [Cork]

Journal title :

PHYSICAL REVIEW APPLIED

Pages :

024052

Publisher :

American Physical Society

Publication date :

2024

ISSN :

2331-7019

HAL domain(s) :

Sciences de l'ingénieur [physics]/Micro et nanotechnologies/Microélectronique
Physique [physics]/Physique [physics]/Physique Numérique [physics.comp-ph]

English abstract : [en]

The efficiency of (In,Ga)N-based light emitting diodes (LEDs) is limited by the failure of holes to evenly distribute across the (In,Ga)N/GaN multi-quantum well stack which forms the active region. To tackle this problem, ...
Show more >The efficiency of (In,Ga)N-based light emitting diodes (LEDs) is limited by the failure of holes to evenly distribute across the (In,Ga)N/GaN multi-quantum well stack which forms the active region. To tackle this problem, it is important to understand carrier transport in these alloys. In this work, we study the impact that random alloy fluctuations have on the distribution of electrons and holes in such devices. To do so, an atomistic tight-binding model is employed to account for alloy fluctuations on a microscopic level and the resulting tight-binding energy landscape forms input to a quantum corrected drift-diffusion model. Here, quantum corrections are introduced via localization landscape theory. Similar to experimental studies in the literature, we have focused on a multi-quantum well system where two of the three wells have the same In content while the third well differs in In content. By changing the order of wells in this ‘multi-color’ quantum well structure and looking at the relative radiative recombination rates of the different emitted wavelengths, we (i) gain insight into the distribution of carriers in such a system and (ii) can compare our findings to trends observed in experiment. We focus on three factors and evaluate the impact that each have on carrier distribution: an electron blocking layer, quantum corrections and random alloy fluctuations. We find that the electron blocking layer is of secondary importance. However, in order to recover experimentally observed features – namely that the p-side quantum well dominates the light emission – both quantum corrections and random alloy fluctuations should be considered. The widely assumed homogeneous virtual crystal approximation fails to capture the characteristic light emission distribution across a multi-quantum well stack.Show less >

Language :

Anglais

Popular science :

Non

ANR Project :

Centre Européen pour les Mathématiques, la Physique et leurs Interactions

Collections :

• Laboratoire Paul Painlevé - UMR 8524

Source :

Harvested from HAL