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arXiv · 2607.22337

Klein tunneling through an asymmetric barrier: Symmetric transmission and directional pair creation

Andre G. Campos·Denys I. Bondar
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Abstract

We prove that the transmission probability for the Klein tunneling through a spatially asymmetric barrier is the same for left and right incidence whenever each asymptotic lead carries a single propagating channel per direction. Time-dependent Wigner-function simulations confirm this and locate the missing directionality in the barrier's interior, where a sharp edge generates several times more under-barrier negative-energy population than a smooth one. Directional control in the Klein regime therefore resides in pair production rather than in the transmitted current.

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Andre G. Campos, Denys I. Bondar. 2026-07-24. Klein tunneling through an asymmetric barrier: Symmetric transmission and directional pair creation. https://arxiv.org/abs/2607.22337

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