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arXiv · 1107.5352

High magnetoresistance at room temperature in p-i-n graphene nanoribbons due to band-to-band tunneling effects

Gengchiau Liang·S. Bala kumar·M. B. A. Jalil·S. G. Tan
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Abstract

A large magnetoresistance effect is obtained at room-temperature by using p-i-n armchair-graphene-nanoribbon (GNR) heterostructures. The key advantage is the virtual elimination of thermal currents due to the presence of band gaps in the contacts. The current at B=0T is greatly decreased while the current at B>0T is relatively large due to the band-to-band tunneling effects, resulting in a high magnetoresistance ratio, even at room-temperature. Moreover, we explore the effects of edge-roughness, length, and width of GNR channels on device performance. An increase in edge-roughness and channel length enhances the magnetoresistance ratio while increased channel width can reduce the operating bias.

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Gengchiau Liang, S. Bala kumar, M. B. A. Jalil, S. G. Tan. 2011-07-26. High magnetoresistance at room temperature in p-i-n graphene nanoribbons due to band-to-band tunneling effects. https://doi.org/10.1063/1.3624459

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