“…In the following part, we give a comprehensive analysis of the enhancement of the light‐graphene interaction. For 2D monolayer graphene, only the electric field components that are parallel to its surface contribute to the light absorption in graphene, [
42 ] and thus we define the effective interaction factor (EIF) as the ratio between the integral of the electric field intensity components parallel to the waveguide surface over the graphene region and the integral of the total electric field intensity over the entire simulation region, [
43 ] i.e.,
where | E ∥ ( x , y )| 2 = | E x | 2 + | E z | 2 and | E ⊥ ( x , y )| 2 = | E y | 2 are the field intensity components parallel and perpendicular to the graphene sheet, respectively, G is the area of the graphene region shown by the red dashed box in Figure 1b,c, and S is the area of the entire simulation region shown by the blue dashed box in Figure 1c. EIF represents the light‐graphene interaction strength, which is proportional to the power of the optical field confined in the graphene region.…”