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arXiv · 1304.5589

Ballistic collective group delay and its Goos-Hänchen component in graphene

Yu Song·Han-Chun Wu
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Abstract

We theoretically investigate the experimental observable of the ballistic collective group delay (CGD) of all the particles on the Fermi surface in graphene. First, we reveal that, lateral Goos-Hänchen (GH) shifts along barrier interfaces contribute an inherent component in the individual group delay (IGD). Then, by linking the complete IGD to spin precession through a dwell time, we suggest that, the CGD and its GH component can be electrostatically measured by a conductance difference in a spin-precession experiment under weak magnetic fields. Such an approach is feasible for almost arbitrary Fermi energy. We also indicate that, it is a generally nonzero self-interference delay that relates the IGD and dwell time in graphene.

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Yu Song, Han-Chun Wu. 2013-04-20. Ballistic collective group delay and its Goos-Hänchen component in graphene. https://doi.org/10.1088/0953-8984%2F25%2F35%2F355301

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