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arXiv · 0810.0936

Coherent electronic transport through graphene constrictions: sub-wavelength regime and optical analogies

Pierre Darancet·Valerio Olevano·Didier Mayou
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Abstract

Graphene two-dimensional nature combined with today lithography allows to achieve nanoelectronics devices smaller than the Dirac electrons wavelength. Here we show that in these graphene subwavelength nanodevices the electronic quantum transport properties present deep analogies with classical phenomena of subwavelength optics. By introducing the concept of electronic diffraction barrier to represent the effect of constrictions, we can easily describe the rich transport physics in a wealth of nanodevices: from Bethe and Kirchhoff diffraction in graphene slits, to Fabry-Perot interference oscillations in nanoribbons. The same concept applies to graphene quantum dots and gives new insigth into recent experiments on these systems.

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Pierre Darancet, Valerio Olevano, Didier Mayou. 2008-10-06. Coherent electronic transport through graphene constrictions: sub-wavelength regime and optical analogies. https://doi.org/10.1103/physrevlett.102.136803

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