Third-order nonlinear optical properties of ADP crystal. (16th May 2018) - Wang, Mengxia
Abstract: By using the Z-scan method, we investigated the third-order nonlinear optical (NLO) properties of ADP crystal at different wavelengths (355, 532, and 1064 nm) and different orientations ([001], [100], [110], I and II). The experimental data were fitted by NLO theory, to give out the two photon absorption (TPA) coefficient β 2 and the nonlinear refractive index n 2 . When the light source changed from a 40 ps, 1064 nm fundamental laser to a 30 ps, 355 nm third-harmonic-generation (THG) laser, the β 2 value increased about 5 times (0.2 × 10 −2 → 1 × 10 −2 cm GW −1 ), and the n 2 value increased about 1.5 times (1.5 × 10 −16 → 2.2 × 10 −16 cm 2 W −1 ). Among all of the orientations, the [110] sample exhibits the smallest β 2, and the second smallest n 2 . It indicates that this orientation and its surroundings will be the preferred directions for high-power laser applications of ADP crystal.