Shape Change and Color Gamut in Gold Nanorods, Dumbbells, and Dog Bones

Abstract

It is shown here that deviations from prolate ellipsoidal shape have a significant effect on the optical properties of gold nanorods. Transitions from rods to ‘dumbbell’, or ‘phi’-shaped particles lead to a shift in the longitudinal plasmon peak in the blue and red directions respectively. Development of ‘dog-bone’ shapes leads to a red-shift and to the development of a third peak. A broad and flexible color gamut can be obtained.