PbTiO_3薄膜的非线性光学性质研究

Study on Optical Nonlinearity in PbTiO_3 Film

用射频磁控溅射系统在α Al2O3衬底上制备了具有钙钛矿结构的PbTiO3薄膜. 用光学透射测量方法得到了该薄膜材料的基本光学常数 (带隙、线性折射率、线性吸收系数). 利用Z 扫描技术确定的非线性折射系数n2的符号及大小为-2. 8×10-7 esu,双光子吸收系数为 51. 8cm/GW. 这些结果表明PbTiO3铁电薄膜在非线性光学上具有潜在的应用前景.

This study fabricated PbTiO_(3) thin film with pervoskite structure on α-Al_(2)O_(3) substrate using a RF-magnetron sputtering system. The band gap, linear refractive indices and absorption coefficients fundamental optical constants of the film were obtained through optical transmittance measurements. The magnitude and sign of the nonlinear refractive index n_(2) were determined to be as high as -2.8×10^(-7) esu by using the single beam Z-scan technique with a picosecond laser. The two-photon absorption coefficient of the PbTiO_(3) film was determined to be 51.8 cm/GW. All these results show that PbTiO_(3) ferroelectric thin films have potential applications in nonlinear optics.