Measurements of giant second harmonic generation from vertically aligned silicon nanowires

Abstract

In this paper, we present our recent measurement of second harmonic generation (SHG) from silicon nanowires which are vertically aligned. The SHG shows a great enhancement due to the increase of the surface area which breaks the symmetry of silicon lattice and increase the surface SHG. A high SHG is also obtained in counter polarization for both S and P polarization excitation. An enhancement of 80 times is also observed. This huge enhancement opens the door for novel applications including frequency mixing and frequency generation for various novel nonlinear application of silicon based devices.