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arXiv · 0910.1950

Light-induced valley currents and magnetization in graphene rings

A. S. Moskalenko·J. Berakdar
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Abstract

We study the non-equilibrium dynamics in a mesoscopic graphene ring excited by picoseconds shaped electromagnetic pulses. We predict an ultrafast buildup of charge polarization, currents and orbital magnetization. Applying the light pulses identified here, non-equilibrium valley currents are generated in a graphene ring threaded by a stationary magnetic flux. We predict a finite graphene ring magnetization even for a vanishing charge current; the magnetization emerges due to the light-induced difference of the valley populations.

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A. S. Moskalenko, J. Berakdar. 2009-10-10. Light-induced valley currents and magnetization in graphene rings. https://doi.org/10.1103/physrevb.80.193407

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