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arXiv · 0905.4278

Prefect Klein tunneling in anisotropic graphene-like photonic lattices

Omri Bahat-Treidel·Or Peleg·Mark Grobman·Nadav Shapira·T. Pereg-Barnea·Mordechai Segev
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Abstract

We study the scattering of waves off a potential step in deformed honeycomb lattices. For small deformations below a critical value, perfect Klein tunneling is obtained. This means that a potential step in any direction transmits waves at normal incidence with unit transmission probability, irrespective of the details of the potential. Beyond the critical deformation, a gap in the spectrum is formed, and a potential step in the deformation direction reflects all normal-incidence waves, exhibiting a dramatic transition form unit transmission to total reflection. These phenomena are generic to honeycomb lattice systems, and apply to electromagnetic waves in photonic lattices, quasi-particles in graphene, cold atoms in optical lattices.

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Omri Bahat-Treidel, Or Peleg, Mark Grobman, Nadav Shapira, T. Pereg-Barnea, Mordechai Segev. 2009-05-26. Prefect Klein tunneling in anisotropic graphene-like photonic lattices. https://doi.org/10.1103/physrevlett.104.063901

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