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Updated: Nov 15, 2025
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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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New two-dimensional arsenene polymorph predicted by first-principles calculation: robust direct bandgap and enhanced
Yifan Gao1, Zixin Cheng2, Minru Wen1
1School of Physics and Optoelectronic Engineering, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
Nanotechnology
|March 2, 2021
Summary
Researchers predict a new, stable 2D arsenic allotrope, delta-arsenic (δ-As), with a direct bandgap. This material
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid State Chemistry
Background:
- Previous research predicted 2D monolayer arsenic structures.
- Existing models often indicated indirect bandgaps for such materials.
Purpose of the Study:
- To predict and characterize a new, stable polymorph of 2D monolayer arsenic.
- To investigate the electronic and optical properties of the novel arsenic allotrope.
Main Methods:
- Computational materials prediction.
- Density Functional Theory (DFT) calculations.
Main Results:
- A new, thermodynamically and kinetically stable 2D arsenic polymorph, denoted as δ-As, was predicted.
- The δ-As monolayer exhibits a direct bandgap, unlike previously predicted structures.
- Applying tensile strain along the zigzag direction tunes the bandgap of δ-As from 1.83 eV to 0 eV.
Conclusions:
- The novel δ-As monolayer presents a promising 2D material with tunable electronic properties.
- The direct bandgap and strain-tunable characteristics make δ-As suitable for optoelectronic applications, including solar cells and photodetectors.
Keywords:
artificial intelligence materials designatomically thin arseneneelectronic propertiesoptoelectronics deviceMore Related Videos
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