中文摘要：

合成了两种新的金属双噻吩类复合物：（苄基三乙基铵）双（1,3-二硫杂环戊烯-2-硫酮-4,5-二巯基）-金（BTEAADT）和（苄基三乙基铵）双（1,3-二硫杂环戊烯-2-硫酮-4,5-二巯基）-镍（BTEANDT）.采用Z扫描方法,在皮秒脉冲下,分别测试了两种材料的乙腈溶液在532和1064nm的三阶非线性光学特性.Z扫描的结果表明,BTEAADT的乙腈溶液在532nm具有反饱和吸收效应,在1064nm非线性吸收效应可以忽略且在两种波长都有自散焦效应,三阶非线性折射率为负值.BTEANDT的乙腈溶液在532nm非线性吸收效应可以忽略,在1064nm具有饱和吸收效应且在两种波长都有自聚焦效应,三阶非线性折射率为正值.分析了造成这种差异的原因.经过计算得到了两种材料在532和1064nm的三阶非线性折射率,三阶非线性吸收系数,三阶非线性极化率和超极化率.BETAADT的非线性折射率在532nm为-1.685×10-18m2·W^-1,在1064nm为-1.459×10-18m2·W^-1;BTEANDT的非线性折射率在532nm为1.452×10-18m2·W^-1,在1064nm为7.311×10-18m2·W^-1.两种材料的三阶非线性吸收系数,三阶非线性极化率和超极化率的数量级分别是10-11m·W^-1,10-13esu和10-31esu.结果表明这两种材料在非线性光学领域有潜在的应用价值.

英文摘要：

Two novel 1,3-dithiole-2-thione-4,5-dithiolate compounds,benzyltriethylamine bis（2-thioxo-1,3- dithiole-4,5-dithiolato）aurate（III）（BTEAADT）and benzyltriethylamine bis（2-thioxo-1,3-dithiole-4,5- dithiolato）nickel（III）（BTEANDT）,were prepared and their optical nonlinearities in acetonitrile solutions at 532 and 1064 nm were investigated using the Z-scan technique with picosecond laser pulses.The Z-scan curves revealed that BTEAADT exhibited mainly reverse saturable absorption at 532 nm,negligible nonlinear absorption at 1064 nm,and a self-defocusing effect at both wavelengths,which meant that the third-order nonlinear refractive index was negative.BTEANDT exhibited saturable absorption at 1064 nm, negligible nonlinear absorption at 532 nm,and a self-focusing effect at both wavelengths,which meant that the third-order nonlinear refractive index was positive.The reason for these different phenomena was analyzed.The third-order nonlinear refractive index,the third-order nonlinear absorption coefficient,the third-order nonlinear susceptibility,and the hyperpolarizability were obtained at 532 and 1064 nm.The nonlinear refractive indices were-1.685×10 -18 m 2 ·W^-1 at 532 nm and-1.459×10 -18 m 2 ·W^-1 at 1064 nm for BTEAADT and 1.452×10 -18 m 2 ·W^-1 at 532 nm and 7.311×10 -18 m 2 ·W^-1 at 1064 nm for BETANDT.The magnitudes of the third-order nonlinear absorption coefficient,the third-order nonlinear susceptibility,and the hyperpolarizability were 10 -11 m·W^-1 ,10 -13 esu,and 10 -31 esu,respectively.All these results suggest that these materials are promising candidates for application in the nonlinear optical area.