Acceptance bandwidths for type I QPM frequency doubling with different polarization in bulk PPLN

In this paper, we investigate the acceptance bandwidths due to different polarization of fundamental waves for type I quasi-phase-matched (QPM) second-harmonic-generation (SHG) in bulk periodically poled lithium niobate (PPLN) theoretically, which are determined by the departures from ideal quasi-phase matching in periodicity, wavelength and temperature. This analysis is useful for establishing fabrication tolerances for practical QPM bulk PPLN device. The numerical comparisons of acceptance bandwidths between type I QPM SHG Ez(omega )->Ez2(omega ) and Ey(omega )Ey(omega )->Ez2(omega )(oo->e) at 150 degree(s)C in bulk PPLN are first presented. The grating periods for two various polarization interactions are given. The result shows that the acceptance bandwidths can be significantly enhanced by the use of the perpendicular polarization. Furthermore, the limitation of input fundamental wavelength for Ey(omega )Ey(omega )->Ez2(omega )(oo->e) QPM SHG in bulk PPLN is discussed.