Effect of Fabry-Perot interference on second harmonic generation in a GaAs plate

The transmitted and reflected second harmonic generation is computed for a parallel-plate Fabry-Perot structure including all the effects of interference and multiple reflections. As a function of wavelength, the spectra consist of rapid Fabry-Perot oscillations superimposed on the more slowly varying coherence-length fringes. The harmonic generation from a 97.5-μm-thick GaAs plate, obtained using a fundamental near 2μm from a wavelength-tunable parametric oscillator, is in good agreement with the theoretical calculations.