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arXiv · 2312.16207

Massive Klein Tunneling in Topological Photonic Crystals

Keiji Nakatsugawa·Xiao Hu
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Abstract

Klein's paradox refers to the transmission of a relativistic particle through a high potential barrier. Although it has a simple resolution in terms of particle-to-antiparticle tunneling (Klein tunneling), debates on its physical meaning seem lasting partially due to the lack of direct experimental verification. In this article, we point out that honeycomb-type photonic crystals (PhCs) provide an ideal platform to investigate the nature of Klein tunneling, where the effective Dirac mass can be tuned in a relatively easy way from a positive value (trivial PhC) to a negative value (topological PhC) via a zero-mass case (PhC graphene). Especially, we show that analysis of the transmission between domains with opposite Dirac masses -- a case hardly be treated within the scheme available so far -- sheds new light on the understanding of the Klein tunneling.

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Keiji Nakatsugawa, Xiao Hu. 2023-12-23. Massive Klein Tunneling in Topological Photonic Crystals. https://doi.org/10.1364/optcon.515300

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