Flat-lens focusing of electrons on the surface of a topological insulator

@article{Hassler2010FlatlensFO,
  title={Flat-lens focusing of electrons on the surface of a topological insulator},
  author={Fabian Hassler and A. Akhmerov and C. W. J. Beenakker},
  journal={Physical Review B},
  year={2010},
  volume={82},
  pages={125423}
}
We propose the implementation of an electronic Veselago lens on the conducting surface of a three-dimensional topological insulator (such as Bi{sub 2}Te{sub 3}). The negative refraction needed for such a flat lens results from the sign change in the curvature of the Fermi surface, changing from a circular to a snowflakelike shape across a sufficiently large electrostatic potential step. No interband transition (as in graphene) is needed. For this reason, and because the topological insulator… 

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