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arXiv · 1305.4823

Magnetoplasmons in quasi-neutral epitaxial graphene nanoribbons

J. M. Poumirol·W. Yu·X. Chen·C. Berger·W. A. de Heer·M. L. Smith·T. Ohta·W. Pan·M. O. Goerbig·D. Smirnov·Z. Jiang
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Abstract

We present infrared transmission spectroscopy study of the inter-Landau-level excitations in quasi-neutral epitaxial graphene nanoribbon arrays. We observed a substantial deviation in energy of the $L_{0(-1)}$$\to$$L_{1(0)}$ transition from the characteristic square root magnetic-field dependence of two-dimensional graphene. This deviation arises from the formation of upper-hybrid mode between the Landau level transition and the plasmon resonance. In the quantum regime the hybrid mode exhibits a distinct dispersion relation, markedly different from that expected for conventional two-dimensional systems and highly doped graphene.

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J. M. Poumirol, W. Yu, X. Chen, C. Berger, W. A. de Heer, M. L. Smith, T. Ohta, W. Pan, M. O. Goerbig, D. Smirnov, Z. Jiang. 2013-06-29. Magnetoplasmons in quasi-neutral epitaxial graphene nanoribbons. https://doi.org/10.1103/physrevlett.110.246803

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