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Rojas WY, Villegas CEP, Rocha AR. Spin-orbit coupling prevents spin channel suppression of transition metal atoms on armchair graphene nanoribbons. Phys Chem Chem Phys 2018; 20:29826-29832. [PMID: 30467570 DOI: 10.1039/c8cp05337e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We investigate the spin-dependent electronic and transport properties of armchair graphene nanoribbons including spin-orbit coupling due to the presence of nickel and iridium adatoms by using ab initio calculations within the spin-polarized density functional theory and non-equilibrium Green's function formalism. Our results indicate that the intensity of the spin-flip precession is a direct consequence of the relaxed adsorption sites of the adatoms. We point out that d orbitals of Ni and Ir result in strong dependence on the spin-conserved and spin-flip transmission probabilities. In particular, we show that the presence of spin-orbit coupling can lead to an enhancement of the transmission probabilities especially around resonances arising due to weak coupling with specific orbitals.
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Affiliation(s)
- W Y Rojas
- School of Electronic Engineering, Bangor University, Bangor LL57 1UT, UK
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Rojas WY, Winter AD, Grote J, Kim SS, Naik RR, Williams AD, Weiland C, Principe E, Fischer DA, Banerjee S, Prendergast D, Campo EM. Strain and Bond Length Dynamics upon Growth and Transfer of Graphene by NEXAFS Spectroscopy from First-Principles and Experiment. Langmuir 2018; 34:1783-1794. [PMID: 29286662 DOI: 10.1021/acs.langmuir.7b03260] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
As the quest toward novel materials proceeds, improved characterization technologies are needed. In particular, the atomic thickness in graphene and other 2D materials renders some conventional technologies obsolete. Characterization technologies at wafer level are needed with enough sensitivity to detect strain in order to inform fabrication. In this work, NEXAFS spectroscopy was combined with simulations to predict lattice parameters of graphene grown on copper and further transferred to a variety of substrates. The strains associated with the predicted lattice parameters are in agreement with experimental findings. The approach presented here holds promise to effectively measure strain in graphene and other 2D systems at wafer levels to inform manufacturing environments.
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Affiliation(s)
- W Y Rojas
- School of Electronic Engineering, Bangor University , Bangor LL57 1UT, United Kingdom
| | - A D Winter
- School of Electronic Engineering, Bangor University , Bangor LL57 1UT, United Kingdom
| | - J Grote
- Materials and Manufacturing Directorate, Air Force Research Laboratory , Wright-Patterson AFB, Ohio 45433, United States
| | - S S Kim
- Materials and Manufacturing Directorate, Air Force Research Laboratory , Wright-Patterson AFB, Ohio 45433, United States
| | - R R Naik
- Materials and Manufacturing Directorate, Air Force Research Laboratory , Wright-Patterson AFB, Ohio 45433, United States
| | - A D Williams
- Materials and Manufacturing Directorate, Air Force Research Laboratory , Wright-Patterson AFB, Ohio 45433, United States
| | - C Weiland
- Synchrotron Research, Inc. , Melbourne, Florida 32901, United States
| | - E Principe
- Synchrotron Research, Inc. , Melbourne, Florida 32901, United States
| | - D A Fischer
- National Institute of Standards and Technology , Gaithersburg, Maryland 20899, United States
| | - S Banerjee
- Departments of Chemistry and Materials Science and Engineering, Texas A&M University , College Station, Texas 77842-3012, United States
| | - D Prendergast
- The Molecular Foundry, Materials Science Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - E M Campo
- School of Electronic Engineering, Bangor University , Bangor LL57 1UT, United Kingdom
- Department of Physics and Astronomy, University of Texas at San Antonio , San Antonio, Texas 78249, United States
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