Persistent currents in absence of magnetic field in graphene nanorings: The ambiguous role of inter valley scattering

Colin Benjamin; A M Jayannavar

doi:10.1063/1.4864615

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arXiv · 1309.5197

Persistent currents in absence of magnetic field in graphene nanorings: The ambiguous role of inter valley scattering

Colin Benjamin·A M Jayannavar

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Abstract

Persistent currents can arise in normal-metal rings due to a magnetic flux threading the ring in equilibrium. However, can persistent currents arise in absence of magnetic flux in the same normal-metal rings? Yes they can but in a non-equilibrium set-up. This is known as current magnification. In this work we show that current magnification can be seen in graphene nanorings. Further, graphene can have electrons polarized with a valley quantum number. Electron scattering between valleys can have a non-trivial effect on these persistent currents including inducing a sign change and generating them for parameters where none existed to begin with.

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Colin Benjamin, A M Jayannavar. 2014-01-27. Persistent currents in absence of magnetic field in graphene nanorings: The ambiguous role of inter valley scattering. https://doi.org/10.1063/1.4864615

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