Contribution of higher order plasmonic modes on optical absorption enhancement in amorphous silicon thin films

For an array of regularly patterned interacting spherical Ag nano particles over an amorphous silicon (a-Si:H) layer of thickness 200 nm, we use Finite Difference Time Domain method for studying the plasmonic absorption enhancement within the a-Si:H layer over the visible range (400 nm–750 nm). The nano particle radius (R) has been varied from 100 nm to 200 nm and array period (D) from 320 nm to 500 nm satisfying the criteria 2R