Optimization of parameters and characteristics of broadband thz absorbers based on 2$d$ lattices of graphene ribbons on multilayer substrates

A multilayer two-dimensional periodic arrays of graphene micro-ribbons, which absorbs almost 100% of the energy of incident wave at the resonance of the surface plasmon-polariton, has been theoretically investigated. To increase the bandwidth of the absorbers, it is proposed to place 2–3 parallel graphene ribbons with close lengths in the unit cell of the 2$d$ array.