Non-linear optical studies of nickel dithiolene complexes

The third-order optical non-linearity, χ(3), linear absorption coefficient, α, and the ratio of the real to imaginary parts of χ(3)have been measured at 1.06µm for a range of nickel dithiolene complexes with absorption bands between 0.77 and 1.06µm. From these data the non-linear retractive index, n2, and the device-based figure of merit, W(=Δnsat/αλ), were calculated. W was found to exceed 2 for materials with absorption maxima below 0.8–0.85µm. The non-linear refractive index of a poly(methyl methacrylate) host doped with 8 × 1019 molecules cm–3 of a nickel dithiolene was also measured and found to be nearly 2 × 10–9cm2 kW–1.