Growth of a new self-frequency-doubling medium: optical superlattice Nd:MgO:LiNbO3 and its laser and nonlinear optical properties

摘要

Abstract: A new multifunctional active medium: optical superlattice Nd:MgO:LiNbO$-3$/, i.e., LiNbO$-3$/ crystal with periodic ferroelectric domain structures, was grown in our laboratory. The absorption and fluorescence spectra of a sample with the modulation period of 7.5 micrometer were carefully measured and show some differences from the results of common Nd:MgO:LiNbO$-3$/ with monodomain structure. Third-order quasi-phase-matched second harmonic generation was also demonstrated to characterize the nonlinear optical properties of the sample. These results indicate that the optical superlattice LiNbO$-3$/ has great potentials for self-frequency-doubling operation using the maximum nonlinear coefficient d$-33$/ of LiNbO$-3$/ and high gain pi polarization at the same time. Pumped by a pulsed dye laser, self-frequency-doubling green light was observed in a cavity with great loss. !15