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arXiv · 1202.3569

Appearance of Negative Differential Conductivity in Graphene Nanoribbons at High-Harmonics

M. Rabiu·S. Y. Mensah·S. S. Abukari
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Abstract

We theoretically study current dynamics of graphene nanoribbons subject to bias dc and ac driven fields. We showed that graphene nanoribbons exhibit negative high-harmonic differential conductivity. Negative differential conductivity appears when bias electric filed is in the neighborhood of applied ac filed amplitude. We also observe both even and odd high-harmonic negative differential conductivity at wave mixing of two commensurate frequencies. The even harmonics are more pronounced than the odd harmonics. A possible use of the present method for generating terahertz frequencies at even harmonics in graphene is suggested.

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M. Rabiu, S. Y. Mensah, S. S. Abukari. 2012-03-11. Appearance of Negative Differential Conductivity in Graphene Nanoribbons at High-Harmonics. https://doi.org/10.4236/graphene.2013.22009

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