Half-metallic graphene nanoribbons
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TLDR
In this article, it was shown that if in-plane homogeneous electric fields are applied across the zigzag-shaped edges of the graphene nanoribbons, their magnetic properties can be controlled by the external electric fields.Abstract:
Electrical current can be completely spin polarized in a class of materials known as half-metals, as a result of the coexistence of metallic nature for electrons with one spin orientation and insulating nature for electrons with the other. Such asymmetric electronic states for the different spins have been predicted for some ferromagnetic metals--for example, the Heusler compounds--and were first observed in a manganese perovskite. In view of the potential for use of this property in realizing spin-based electronics, substantial efforts have been made to search for half-metallic materials. However, organic materials have hardly been investigated in this context even though carbon-based nanostructures hold significant promise for future electronic devices. Here we predict half-metallicity in nanometre-scale graphene ribbons by using first-principles calculations. We show that this phenomenon is realizable if in-plane homogeneous electric fields are applied across the zigzag-shaped edges of the graphene nanoribbons, and that their magnetic properties can be controlled by the external electric fields. The results are not only of scientific interest in the interplay between electric fields and electronic spin degree of freedom in solids but may also open a new path to explore spintronics at the nanometre scale, based on graphene.read more
Citations
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Electronic Structures of Porous Graphene, BN, and BC2N Sheets with One- and Two-Hydrogen Passivations from First Principles
TL;DR: In this article, the structural and electronic properties of monolayer porous graphene (C), BN, and BC2N sheets with one-hydrogen passivation were investigated. But the porous BN sheet has a larger band gap than the porous C one, whereas the porous BC 2N sheets have variable band gaps depending on the atomic arrangements of B, C and N atoms.
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Third-order nonlinear optical properties of trigonal, rhombic and bow-tie graphene nanoflakes with strong structural dependence of diradical character
Kyohei Yoneda,Masayoshi Nakano,Ryohei Kishi,Hideaki Takahashi,Akihiro Shimizu,Takashi Kubo,Kenji Kamada,Koji Ohta,Benoît Champagne,Edith Botek +9 more
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References
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