Second harmonic generation of metal nanoparticles under tightly focused illumination
Sun Jing-Wei1, Wang Xiang-Hui1, †, , Chang Sheng-Jiang1, Zeng Ming2, Zhang Na1
       

Phase distributions of the component Ei,x of (a) PW and (b) focused field in the x–z plane; (c) axial phase shift of the focused field.