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Origin of multiple band gap values in single width nanoribbons
Deepika1, Shailesh Kumar2, Alok Shukla3
1Department of Physics, Indian Institute of Technology Ropar, Rupnagar-140001, India.
Scientific Reports
|November 4, 2016
Summary
Researchers discovered that shifting passivating atoms at the edges of nanoribbons modifies potential wells, explaining multiple band gaps in graphene nanoribbons. This finding enables precise tuning of electronic properties for molecular electronics.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Deterministic band gaps are crucial for high-performance molecular electronics.
- Graphene nanoribbons often exhibit multiple, unresolved band gaps despite uniform width, hindering scalable production.
- This variability poses a challenge for creating nanoribbons with predictable properties.
Purpose of the Study:
- To elucidate the origin of multiple band gaps in quasi-one-dimensional nanoribbons of the same width.
- To identify the key factor responsible for variations in electronic properties.
- To provide a mechanism for tuning the electronic behavior of nanoribbons.
Main Methods:
- Theoretical calculations were performed on graphene and silicene nanoribbons.
- The study focused on analyzing modifications in potential well depths within supercells.
- The impact of relative shifting of passivating atoms at nanoribbon edges was investigated.
Main Results:
- A modification in potential well depth, caused by shifting passivating atoms, was identified as the source of multiple band gaps.
- These variations in band gap occur even when nanoribbons have the same width and similar ground state energy.
- The phenomenon was observed in both planar graphene and buckled silicene nanoribbons.
Conclusions:
- Edge engineering, specifically the manipulation of passivating atoms, offers a method to control band gap values.
- This understanding is vital for the scalable production of nanoribbons with tailored electronic functionalities.
- The findings are applicable to various quasi-one-dimensional materials, including bio-molecular chains and organic/inorganic nanoribbons.
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