Figure 4.

A gold NR dimer of r = 29 nm with an aspect ratio of 1.21 and a gap of 14.7 nm irradiated by an x-polarized Gaussian beam of 446 nm in air for Stage IV to VI. (a) ${\parallel E\parallel }^2$ distribution in the x–z cross section of NR dimer at y = 0. (b) The spherification of each elastically deformed NR was subjected to an effective pressure on surface (inward arrows: pressure) due to the surface tension of liquid gold, where color represents the magnitude of normalized displacement. A swelling is caused by surface tension at the upper central zone of each NP.