Graphene  Vol.2 No.2 , April 2013
Appearance of Negative Differential Conductivity in Graphene Nanoribbons at High-Harmonics
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.

Cite this paper
M. Rabiu, S. Y. Mensah and S. S. Abukari, "Appearance of Negative Differential Conductivity in Graphene Nanoribbons at High-Harmonics," Graphene, Vol. 2 No. 2, 2013, pp. 61-65. doi: 10.4236/graphene.2013.22009.
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