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Monovacancy-induced magnetism in graphene bilayers
Sangkook Choi1, Byoung Wook Jeong, Seungchul Kim
1School of Physics and Astronomy, FPRD, and Center for Theoretical Physics, Seoul National University, Seoul 151-747, Republic of Korea. Department of Physics, University of California at Berkeley, Berkeley, CA 94720, USA.
Summary
Vacancy-induced magnetism in graphene bilayers is reduced by about 10% due to interlayer charge transfer. This finding impacts understanding of magnetic defects in 2D materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Chemistry
Background:
- Graphene exhibits unique electronic properties, including magnetism when defects like vacancies are present.
- Understanding defect-induced magnetism is crucial for developing novel electronic and spintronic devices.
Purpose of the Study:
- To investigate the effect of bilayer configuration on vacancy-induced magnetism in graphene.
- To quantify the changes in spin magnetic moments in graphene bilayers with monovacancies.
Main Methods:
- Spin-polarized density functional theory (SP-DFT) calculations were employed.
- Two distinct atomic configurations of graphene bilayers with a monovacancy were analyzed.
Main Results:
- Spin magnetic moments at the monovacancy site decreased by approximately 10% in graphene bilayers compared to a graphene monolayer.
- This reduction was observed for both investigated bilayer configurations.
Conclusions:
- Interlayer charge transfer from the adjacent layer to the layer with the monovacancy significantly reduces localized spin magnetic moments.
- The findings provide insights into the behavior of magnetic defects in multilayer graphene systems.
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