Graphene is increasingly being used in the design of electromagnetic devices. The resistivity of graphene can be adjusted via chemical potential tuning, which truly benefits the implementation of tunable and reconfigurable devices. This paper investigates the switch-like attribute of parasitic graphene surface used in a dipole operating at 0.39 THz. Further, a novel orbital angular moment (OAM) generator with radiation reconfiguration is proposed. Spiral beams carrying variety of OAM modes can be produced easily using the generator.
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