Design of narrowband or broadband absorber by heterostructures including TMDCs and spacers

•Heterostructures containing two TMDC monolayers and two spacers.•Improved absorption comparing to having no spacer.•Spacers, leading to wave localization in TMDC monolayers, cause absorption climb.•Different TMDC monolayers permutation create narrowband or broadband absorbers. Two-dimensional transition metal dichalcogenides materials (TMDCs) have gathered attention because of their special features like absorption. In order to increase absorption in narrowband or broadband wavelength, heterostructures, which consist of two TMDC, monolayers, and spacers, are suggested and probed in the entire visible wavelength range. In this paper, the effectiveness of TMDC monolayers permutation, spacer number, spacer place, spacer thickness, incident angle, and polarization on absorption have been investigated, and concluded that usage of the spacer would almost double the absorption comparing to having no spacer, while the structure is simple. The suggested structure is able to invite attentions to utilize them in devices like optoelectronic and nanophotonic.