Tunable scattered colors over a wide spectrum from a single nanoparticle.

By controlling the thickness of the silver shell, Au-Ag core-shell nanorods with quadruple plasmonic peaks corresponding to red, green, violet and deep violet regions have been prepared. Additionally, under polarized light, we achieved tunability of scattered colors from a single nanoparticle over an exceptionally wide wavelength range. The observed colors include red, orange, yellow, green, blue and purple.