Deep-subwavelength light transmission in hybrid graphene-dielectric slot waveguide

In this paper, a novel hybrid graphene-dielectric slot waveguide (HGDSW) is theoretically proposed. The characteristics of the fundamental hybrid modes (TM polarization) including effective refractive index (n(eff)), normalized mode area (A(eff)/A(0)), propagation length (L-p) and figure of merit are numerically investigated. The results reveal the hybrid mode guided in the proposed HGDSW can be tuned by the key geometric structure parameters and the chemical potential of graphene. Besides, the HGDSW can support low loss and effective deep-subwavelength light transmission in THz wavelength, in conjunction with enhanced overall high performance. Moreover, ultra-low crosstalk between two parallel HGDSWs can be achieved. The HGDSWs reveal the potential capabilities in the ultra-compact photonic integration field.