Third-order opical nonlinearity has been studied in one-dimensional Mott insulators, Sr_2CuO_3, Ca_2CuO_3, and halogen-bridged Ni compounds [Ni(chxn)_2X]Y_2 (X=Br, Cl; Y=Br, Cl,(NO_3)), by electroreflectance (ER) spectroscopy. Im chi~((30)(-omega; 0,0, omega) (ER) is evaluated to be che~((30) approx= 10~(-8) to 10~(-5) esu, which is significantly larger than those of conjugated polymers, 10~(-10) aprox 10~(-8)esu. An analysis of the ER spectral shape reveals that the strong enhancement of nonlinear optical response originates from the large transition dipole moments between nearly degenerate odd and even states.
展开▼
机译：在一维Mott绝缘子，Sr_2CuO_3，Ca_2CuO_3和卤桥Ni化合物[Ni（chxn）_2X] Y_2（X = Br，Cl; Y = Br，Cl，（NO_3））中研究了三阶光学非线性，通过电反射（ER）光谱。 Im chi〜（（30）（-omega; 0,0，ω）（ER）被评估为che〜（（30）大约= 10〜（-8）至10〜（-5）esu，这非常显着大于共轭聚合物的10〜（-10）aprox 10〜（-8）esu。ER光谱形状的分析表明，非线性光学响应的强烈增强来自几乎简并的奇数和奇数之间的大跃迁偶极矩。甚至州。
展开▼
