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arXiv · 1604.02741

Voltage-dependent spin flip in magnetically-substituted graphene nanoribbons: Toward the realization of graphene-based spintronic devices

Gregory Houchins·Charles B. Crook·Jian-Xin Zhu·Alexander V. Balatsky·Jason T. Haraldsen
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Abstract

We examine the possibility of using graphene nanoribbons (GNRs) with directly substituted chromium atoms as spintronic device. Using density functional theory, we simulate a voltage bias across a constructed GNR in a device setup, where a magnetic dimer has been substituted into the lattice. Through this first principles approach, we calculate the electronic and magnetic properties as a function of Hubbard U, voltage, and magnetic configuration. By calculating of the total energy of each magnetic configuration, we determine that initial antiferromagnetic ground state flips to a ferromagnetic state with applied bias. Mapping this transition point to the calculated conductance for the system reveals that there is a distinct change in conductance through the GNR, which indicates the possibility of a spin valve. We also show that this corresponds to a distinct change in the induced magnetization within the graphene.

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Gregory Houchins, Charles B. Crook, Jian-Xin Zhu, Alexander V. Balatsky, Jason T. Haraldsen. 2016-04-10. Voltage-dependent spin flip in magnetically-substituted graphene nanoribbons: Toward the realization of graphene-based spintronic devices. https://doi.org/10.1103/physrevb.95.155450

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