Multiple wavelength generation using aperiodically poled lithium niobate

We present a simple method to design aperiodically poled crystals to obtain multiple nonlinear optical processes simultaneously. We use this technique to design and make an aperiodically poled lithium niobate crystal with which we obtained eight distinct sum-frequency generation processes, and another sample with which we obtained four distinct optical parametric generation processes. We also show that the peak effective nonlinearities of aperiodic crystals designed with this technique are larger and their widths are narrower than what can be obtained with a crystal of the same length with separate sections with well-defined poling periodicities.