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arXiv · 1512.09044

Quasi-Relativistic Doppler Effect and Non-Reciprocal Plasmons in Graphene

Dan S. Borgnia·Trung V. Phan·Leonid S. Levitov
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Abstract

Strong optical nonreciprocity at the nanoscale, relying on extreme one-way modes and backscattering suppression, can enable fundamentally new approaches in optoelectronics and plasmonics. Of special interest is achieving nonreciprocity in systems devoid of magnetic couplings. We describe a new approach based on the plasmonic Doppler effect which takes place for plasmons propagating in the presence of an electrical DC current. Large carrier drift velocities reachable in high-mobility electron systems, such as graphene, can enable strongly nonreciprocal or even fully one-way modes. Striking effects such as mode isolation and one-way transmission in DC-current-controlled Mach-Zehnder interferometers provide clear manifestations of plasmonic nonreciprocity. Phenomena such as plasmon resonance splitting into a doublet, induced by a DC current, afford new ways to generate and exploit unidirectionally propagating plasmon modes.

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Dan S. Borgnia, Trung V. Phan, Leonid S. Levitov. 2015-12-30. Quasi-Relativistic Doppler Effect and Non-Reciprocal Plasmons in Graphene. https://arxiv.org/abs/1512.09044

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