Nitride-Based Quantum Structures in Optoelectronics-A Survey of Colors
Iza Gorczyca1, Tadek Suski1, Piotr Perlin1
1Institute of High Pressures Physics, UNIPRESS, 01-142 Warsaw, Poland.
Materials (Basel, Switzerland)
|July 28, 2026
Summary
This review details advancements in nitride-based quantum structures for optoelectronics, focusing on external quantum efficiency (EQE) improvements in light-emitting diodes (LEDs) and laser diodes across the UV to infrared spectrum.
Area of Science:
- Optoelectronics
- Materials Science
- Solid State Physics
Background:
- Nitride-based quantum structures (GaN, AlN, InN) are fundamental to modern optoelectronic devices like LEDs and laser diodes.
- These structures enable tunable light emission from ultraviolet to infrared via composition, strain, and quantum confinement.
Purpose of the Study:
- To review the performance progress of nitride emitters across the entire spectral range.
- To emphasize the evolution of external quantum efficiency (EQE) and identify limiting factors.
Main Methods:
- Literature review of nitride emitter performance, focusing on InGaN and AlGaN quantum wells.
- Analysis of factors influencing external quantum efficiency (EQE) across different wavelength regions.
- Examination of efficiency droop mechanisms and mitigation strategies.
Main Results:
- Blue InGaN LEDs demonstrate high EQE (60-80%).
- A significant "green gap" limits green InGaN LEDs to 20-35% EQE, with further reductions at longer wavelengths.
- AlGaN-based UV emitters show lower performance due to material challenges, but progress is evident.
Conclusions:
- Device performance is intrinsically linked to nitride quantum structure properties and faces distinct challenges per wavelength.
- Understanding and mitigating EQE limitations, such as efficiency droop, is crucial for future applications.
- Continued research promises enhanced performance and expanded applications for nitride optoelectronics.
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