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arXiv · 1507.04038

Topological cutoff frequency in a slab waveguide: Penetration length in topological insulator walls

Thiago M. Melo·Davidson R. Viana·Winder A. Moura-Melo·Jackson M. Fonseca·Afranio R. Pereira
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Abstract

We study the propagation of electromagnetic (EM) waves in a slab-type waveguide which walls consist of three-dimensional topological insulator (3D TI). The results show that a cutoff frequency with topological stability limits the spectrum that propagates along the waveguide and are in agreement with experimental observations. Our approach also provides a way to measure the penetration length of surface metallic states in 3D TI.

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Thiago M. Melo, Davidson R. Viana, Winder A. Moura-Melo, Jackson M. Fonseca, Afranio R. Pereira. 2015-10-23. Topological cutoff frequency in a slab waveguide: Penetration length in topological insulator walls. https://doi.org/10.1016/j.physleta.2015.12.041

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