Dimensionality dependence of optical nonlinearity and relaxation dynamics in cuprates
Dimensionality dependence of optical nonlinearity and relaxation dynamics in cuprates
复制标题
铜酸盐光学非线性和弛豫动力学的维度依赖性
DOI：
10.1209/epl/i2002-00660-6
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发表时间：
2001
期刊：
影响因子：
1.8
通讯作者：
M. Kuwata
中科院分区：
文献类型：
--
作者：
M. Ashida;Y. Taguchi;Y. Tokura;R. T. Clay;S. Mazumdar;Y. Svirko;M. Kuwata
飞秒泵浦探针测量发现铜酸盐的光学非线性明显的维数依赖性。虽然准一维和二维（一维和二维）铜酸盐的相干双光子吸收（TPA）和线性吸收带几乎重合，但二维的TPA系数比一维的小一个数量级。此外，在一维铜酸盐中观察到光学透明度的皮秒恢复，而在二维铜酸盐中的恢复涉及数十皮秒时间尺度的弛豫通道。实验结果用两波段扩展哈伯德模型解释。
Femtosecond pump-probe measurements find pronounced dimensionality dependence of the optical nonlinearity in cuprates. Although the coherent two-photon absorption (TPA) and linear absorption bands nearly overlap in both quasi–one- and two-dimensional (1D and 2D) cuprates, the TPA coefficient is one order of magnitude smaller in 2D than in 1D. Furthermore, picosecond recovery of optical transparency is observed in 1D cuprates, while the recovery in 2D involves relaxation channels with a time scales of tens of picoseconds. The experimental results are interpreted within the two-band extended Hubbard model.