http://demonstrations.wolfram.com/PhaseMatchingOfSHGInNonlinearOptics/ The Wolfram Demonstrations Project contains thousands of free interactive visualizations, with new entries added daily. This Demonstration studies the phase matching condition of second harmonic generation (SHG) in nonlinear optics. The pump laser wave is given by y = cos(k x). The wave of the second harmonic generation (SHG) is ystandard = cos(2k x) if the phase is matc... Contributed by: R. B. Jin