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arXiv · 1610.00201

Fermionic Lensing in Smooth Graphene P-N Junctions

Vo Tien Phong·Jian Feng Kong
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Abstract

Focusing of electron waves in graphene p-n junctions is a striking manifestation of fermionic negative refraction. We analyze lensing in smooth p-n junctions and find that it differs in several interesting ways from that in the previously studied sharp p-n junctions. Most importantly, while the overall negative-refraction behavior remains unchanged, the image at the focal point undergoes additional broadening due to Klein tunneling in the junction. We develop a theory of image broadening and estimate the effect for practically interesting system parameter values.

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Vo Tien Phong, Jian Feng Kong. 2016-10-01. Fermionic Lensing in Smooth Graphene P-N Junctions. https://arxiv.org/abs/1610.00201

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