The Field Enhancement of the Graphene Triple-Groove Waveguide

A graphene triple-groove waveguide having the function of field enhancement is proposed and investigated in this letter. The waveguide consists of three grooves with the internal faces partially coated with graphene. The field enhancement can be over 2000 times in the middle groove and the electric field can be extremely confined in the grooves. The influences of the structural parameters on field enhancement are also demonstrated by separately changing the parameters in this letter. Thanks to the tunable carrier density of graphene, the field enhancement can be controlled by adjusting the chemical potential of graphene. Finally, graphene is replaced by gold in triple-groove waveguide to discuss the effect of field enhancement. Furthermore, the structure of this graphene triple-groove waveguide is simple and the waveguide may have a great prospect in photoelectric devices and bio-sensing.