Nonlinear Optical Studies of [(C_(4)H_(9))_(4)N][Ni(dmit)_(2)] by Z-Scan Technique

Nonlinear optical properties of an organo-metallic compound[(C_(4)H_(9))_(4)N][Ni(dmit)_(2)](dmit=2−thioxo-1,3-dithiole-4,5-dithiolate),abbreviated as BuNi,dissolved in acetone,are investigated using the Z-scan technique with a 40 ps pulse width at 1064 nm and a 1 ns and 15 ns pulse width at 1053 nm.Strong saturable absorption is found when the sample solution is irradiated by 40 ps and 1 ns laser pulses.When irradiated with a 15 ns laser pulse,a stronger reverse saturable absorption is found.The nonlinear optical absorption coefficients are-1.06×10^(-11),−2.02×10^(-11) and 2.73×10^(−10) m/W,respectively.All the results suggest that BuNi may be a promising candidate in the application of laser pulse compression in the near-infrared waveband.