Half-metallic graphene nanoribbons
Reads0
Chats0
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
More filters
Journal ArticleDOI
Revisiting the Mechanism of Oxidative Unzipping of Multiwall Carbon Nanotubes to Graphene Nanoribbons
TL;DR: It is demonstrated that the oxidative unzipping of MWCNTs is intercalation-driven, not oxidative chemical-bond cleavage as was formerly proposed, and even in highly oxidative media one can obtain nonoxidized GNR products.
Journal ArticleDOI
Ultrathin epitaxial cobalt films on graphene for spintronic investigations and applications
Chi Vo-Van,Zoukaa Kassir-Bodon,Hongxin Yang,Johann Coraux,Jan Vogel,Stefania Pizzini,Pascale Bayle-Guillemaud,Mairbek Chshiev,Laurent Ranno,Valérie Guisset,Philippe David,Violaine Salvador,Olivier Fruchart +12 more
TL;DR: In this article, the growth of flat, epitaxial ultrathin Co films on graphene using pulsed laser deposition was reported, which display perpendicular magnetic anisotropy (PMA) in the thickness range 0.5-1'nm.
Journal ArticleDOI
Carbon nanotube, graphene, nanowire, and molecule-based electron and spin transport phenomena using the nonequilibrium Green's function method at the level of first principles theory.
Woo Youn Kim,Kwang S. Kim +1 more
TL;DR: In this article, the authors developed a program code to investigate the electron transport characteristics for a variety of nanometer scaled devices in the presence of an external bias voltage, particularly focusing on k-point sampling for the realistic modeling of the bulk electrode.
Journal ArticleDOI
How does folding modulate thermal conductivity of graphene
TL;DR: In this article, the thermal transport in folded graphene nanoribbons using molecular dynamics simulations and the non-equilibrium Green's function method was studied and it was found that the thermal conductivity of flat GNNs can be modulated by folding and changing interlayer couplings.
Journal ArticleDOI
Graphene field effect transistor without an energy gap
Min Seok Jang,Hyungjun Kim,Young-Woo Son,Harry A. Atwater,William A. Goddard,William A. Goddard +5 more
TL;DR: The switching mechanism demonstrates that intrinsic graphene can be used in designing logic devices without serious alteration of the conventional field effect transistor architecture and suggests a new variable for the optimization of the graphene-based device—geometry of the gate electrode.
References
More filters
Journal ArticleDOI
Two-dimensional gas of massless Dirac fermions in graphene
Kostya S. Novoselov,A. K. Geim,Sergey V. Morozov,Da Jiang,Mikhail I. Katsnelson,Irina V. Grigorieva,S. V. Dubonos,A. A. Firsov +7 more
TL;DR: This study reports an experimental study of a condensed-matter system (graphene, a single atomic layer of carbon) in which electron transport is essentially governed by Dirac's (relativistic) equation and reveals a variety of unusual phenomena that are characteristic of two-dimensional Dirac fermions.
Journal ArticleDOI
Self-interaction correction to density-functional approximations for many-electron systems
John P. Perdew,Alex Zunger +1 more
TL;DR: In this paper, the self-interaction correction (SIC) of any density functional for the ground-state energy is discussed. But the exact density functional is strictly selfinteraction-free (i.e., orbitals demonstrably do not selfinteract), but many approximations to it, including the local spin-density (LSD) approximation for exchange and correlation, are not.
Journal ArticleDOI
Experimental observation of the quantum Hall effect and Berry's phase in graphene
TL;DR: In this paper, an experimental investigation of magneto-transport in a high-mobility single layer of Graphene is presented, where an unusual half-integer quantum Hall effect for both electron and hole carriers in graphene is observed.
Journal ArticleDOI
Spintronics: a spin-based electronics vision for the future.
Stuart A. Wolf,Stuart A. Wolf,David D. Awschalom,Robert A. Buhrman,J. M. Daughton,S. von Molnar,Michael L. Roukes,Almadena Chtchelkanova,Daryl Treger +8 more
TL;DR: This review describes a new paradigm of electronics based on the spin degree of freedom of the electron, which has the potential advantages of nonvolatility, increased data processing speed, decreased electric power consumption, and increased integration densities compared with conventional semiconductor devices.
Journal ArticleDOI
The SIESTA method for ab initio order-N materials simulation
José M. Soler,Emilio Artacho,Julian D. Gale,Alberto García,Javier Junquera,Javier Junquera,Pablo Ordejón,Daniel Sánchez-Portal +7 more
TL;DR: In this paper, a selfconsistent density functional method using standard norm-conserving pseudopotentials and a flexible, numerical linear combination of atomic orbitals basis set, which includes multiple-zeta and polarization orbitals, was developed and implemented.