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Updated: Feb 20, 2026
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Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
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Electronic and Optical Properties of Two-Dimensional GaN from First-Principles
Nocona Sanders1, Dylan Bayerl1, Guangsha Shi1
1Department of Materials Science and Engineering, University of Michigan , Ann Arbor, Michigan 48109, United States.
Nano Letters
|October 26, 2017
Summary
Atomically thin gallium nitride (GaN) shows tunable light emission. Strain engineering enables deep ultraviolet emission for sterilization and polarized light for displays.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Quantum Chemistry
Background:
- Gallium nitride (GaN) is a key semiconductor for solid-state lighting.
- Atomically thin, two-dimensional (2D) GaN offers unique quantum confinement effects.
- Controlling light emission in 2D GaN is crucial for advanced applications.
Purpose of the Study:
- Investigate electronic, optical, and excitonic properties of monolayer and bilayer 2D GaN.
- Analyze the impact of strain on these properties.
- Compare freestanding 2D GaN with GaN/AlN heterostructures.
Main Methods:
- First-principles calculations.
- Density functional theory (DFT).
- Many-body perturbation theory (MBPT).
Main Results:
- Monolayer 2D GaN exhibits deep ultraviolet emission, suitable for sterilization.
- Bilayer 2D GaN emission matches bulk GaN due to quantum confinement and Stark shift interplay.
- Uniaxial strain induces polarized light emission at room temperature.
Conclusions:
- Strain engineering provides control over 2D GaN's optical properties.
- Few-layer GaN offers tunable light emission for diverse applications.
- Understanding barrier effects in GaN/AlN systems is vital for device design.
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