Graphene spin capacitor for magnetic field sensing

Y. G. Semenov; J. M. Zavada; K. W. Kim

doi:10.1063/1.3462297

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arXiv · 1005.2423

Graphene spin capacitor for magnetic field sensing

Y. G. Semenov·J. M. Zavada·K. W. Kim

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Abstract

An analysis of a novel magnetic field sensor based on a graphene spin capacitor is presented. The proposed device consists of graphene nanoribbons on top of an insulator material connected to a ferromagnetic source/drain. The time evolution of spin polarized electrons injected into the capacitor can be used for an accurate determination at room temperature of external magnetic fields. Assuming a spin relaxation time of 100 ns, magnetic fields on the order of $\sim 10$ mOe may be detected at room temperature. The observational accuracy of this device depends on the density of magnetic defects and spin relaxation time that can be achieved.

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Y. G. Semenov, J. M. Zavada, K. W. Kim. 2010-05-13. Graphene spin capacitor for magnetic field sensing. https://doi.org/10.1063/1.3462297

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