Absorption enhancement and spectrum selectivity of refractory plasmonic nanostructures

We demonstrate a broadband spectrum absorber using random structures on refractory plasmonic material (Tungsten) resulting in the absorption efficiency over 90% in the wavelength range from 200 nm to 1100 nm. Numerical simulations for the structure with same parameters agree well with the experimental results. Random nanostructures provide more freedom for enhancing absorption and spectrum selectivity than periodic nanostructures.