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

Musah Rabiu, Samuel Y. Mensah, Sulemana S. Abukari

Department of Applied Physics, University for Development Studies, Navrongo, Ghana.
Physics Department, Center for Laser and Fiber Optics, University of Cape Coast, Cape Coast, Ghana.

DOI: 10.4236/graphene.2013.22009                

Abstract

We theoretically study current dynamics of graphene nanoribbons subject to DC-AC driven fields. We show that graphene exhibits negative differential conductivity (NDC) at high-harmonics. NDC occurs in the neighborhood where a constant electric field is equal to amplitude of ac field. We also observe NDC at both even and odd harmonics and 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.

Keywords

Graphene Nanoribbon; Energy Spectrum; Electronic Conductivity; Terahertz; Negative Differential Conductivity

Conflicts of Interest

The authors declare no conflicts of interest.

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