Chromatic tuning of plasmon resonance of tri-layered composites: silver, gold and copper nanoparticles for optical thin film colour filter

The authors describe an approach to control colour shades by varying the volume fractions of three metal nanoparticles (NPs), Cu, Au and Ag, of fixed size and shape. The NPs were designed to match the absorption peaks of the three primary colours. Using the dynamic Maxwell Garnett equation, an analytical model is extracted that calculates the volume fraction value of each metal for the desired transmission red, green and blue values. The model considers the cross-talk between colours because of the broadening of the plasmon peaks. Maximum error of 10% was observed when producing secondary colour and grey shades.