Second-harmonic susceptibility enhancement in Gallium nitride nanopillars

Second-harmonic generation (SHG) from single GaN nanpoillar is reported. A model for the SHG processes in the GaN nanopillar as a function of diameter is presented; the analysis showed quantitatively that the SHG is dominated by its surface area. The effective second order nonlinear optical susceptibility increases as the diameter of the GaN nanopillar decreases, reaching a value of 136 pm/V at 150nm diameter, making them attractive for modulator applications.