(a) Schematic of a spherical Ag nanoparticle with the radius of 100 nm attached on a cylindrical Ag nanowire with the radius of 60 nm and the length of 6 μm under illumination of circularly polarized light. The incident light propagates along the z-axis, the wavelength is 671 nm. Under (b₁), (b₂) LCP and (c₁), (c₂) RCP illumination, P^O and S of the scattering light displayed at the x–y and y–z planes crossing the spherical surface. The direction of P^O is relative to the Ag NW axis. The color in the Ag NW represents the electric field of SPPs propagating along the NW. The intensity meter is shown at the right.