1. A method of measuring a second-order optical nonlinearity profile of a sample, the method comprising: providing the sample having the second-order optical nonlinearity profile; placing a surface of the sample in proximity to a surface of a supplemental sample, wherein the sample and supplemental sample form a composite sample having a symmetric second-order optical nonlinearity profile; measuring a Fourier transform of the symmetric second-order optical nonlinearity profile; and calculating an inverse Fourier transform of the measured Fourier transform, wherein the calculated inverse Fourier transform provides information regarding the second-order optical nonlinearity profile.