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arXiv · 2509.23096

Evanescent-mode-assisted Klein tunneling in dual-gated bilayer graphene

Yupeng Huang·W. Zeng
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Abstract

We theoretically investigate the electron tunneling in dual-gated bilayer graphene-based $n/p$ junctions. It is shown that a band gap is introduced by tuning the gate voltage, which modifies the pseudospin polarization and breaks anti-Klein tunneling at normal incidence. Specifically, when the pseudospin polarization vectors for the propagating and evanescent wave modes on the left and right regions of the junction are orthogonal, a revival of Klein tunneling is achieved. The Berry phase associated with Klein tunneling in dual-gated bilayer graphene is not limited to $\pi$ but varies with the junction parameters. Furthermore, the Klein tunneling is accompanied by a $\pi$ jump in the reflection phase around the normal incidence.

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Yupeng Huang, W. Zeng. 2025-09-27. Evanescent-mode-assisted Klein tunneling in dual-gated bilayer graphene. https://doi.org/10.1103/wk4v-k4f2

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