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arXiv · 0910.2657

Hartman effect and spin precession in graphene

R. A. Sepkhanov·M. V. Medvedyeva·C. W. J. Beenakker
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Abstract

Spin precession has been used to measure the transmission time τover a distance L in a graphene sheet. Since conduction electrons in graphene have an energy-independent velocity v, one would expect τ> L/v. Here we calculate that τ< L/v at the Dirac point (= charge neutrality point) in a clean graphene sheet, and we interpret this result as a manifestation of the Hartman effect (apparent superluminality) known from optics.

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R. A. Sepkhanov, M. V. Medvedyeva, C. W. J. Beenakker. 2009-12-24. Hartman effect and spin precession in graphene. https://doi.org/10.1103/physrevb.80.245433

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