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arXiv · 2407.07377

Pseudospin-filter tunneling of massless Dirac fermions

Z. D. Li·W. Zeng
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Abstract

The tunneling of the massless Dirac fermions through a vector potential barrier are theoretically investigated, where the vector potential can be introduced by the very high and very thin (delta-function) magnetic potential barriers. We show that, distinct from the previously studied electric barrier tunneling, the vector potential barriers are more transparent for pseudospin-1/2 Dirac fermions but more obstructive for pseudospin-1 Dirac fermions. By tuning the height of the vector potential barrier, the pseudospin-1/2 Dirac fermions remain transmitted, whereas the transmission of the pseudospin-1 Dirac fermions is forbidden, leading to a pseudospin filtering effect for massless Dirac fermions.

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Z. D. Li, W. Zeng. 2024-07-10. Pseudospin-filter tunneling of massless Dirac fermions. https://arxiv.org/abs/2407.07377

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