A new scheme for nondestructive characterization of quasi-phase-matching grating structures and temperature gradients through inverse Fourier theory using second-harmonic-generation experiments is proposed. By inserting a mirror to reflect the signals back through the sample, we show how it is possible to retrieve the relevant information by measuring only the generated second-harmonic power, avoiding more complicated phase measurements. The potential of the scheme is emphasized through theoretical and numerical investigations in the case of periodically poled lithium niobate bulk crystals.
© 2004 Optical Society of America
Steffen Kjær Johansen and Pascal Baldi, "Characterization of quasi-phase-matching gratings in quadratic media through double-pass second-harmonic power measurements," J. Opt. Soc. Am. B 21, 1137-1145 (2004)