2-cyclooctylamino-5-nitropyridine, a new nonlinear optical crystal with orthorhombic symmetry

A new nonlinear optical crystal 2-cyclooctylamino-5-nitropyridine (COANP) with point group symmetry mm2 has been grown by a temperature difference solution growth technique. Its linear and nonlinear optical properties have been investigated. The refractive indices na =1.702, nb =1.847, and nc =1.681 (λ=550 nm) and the nonlinear optical susceptibilities d31 and d33 (λω =1.06 μm) have been determined. Type I phase matching for Nd lasers (λ=1.06 μm) has been demonstrated for the configuration using a combination of d31 and d 32 by angle tuning. A peak efficiency η=P 2ω/Pω =3.6% has been observed with a 0.90-mm-thick crystal and a fundamental power Pω =560 W.