摘要
采用sol-gel方法在石英玻璃衬底上制备出α轴取向的多晶Bi_4Ti_3O_(12)(BIT)薄膜,根据透射谱曲线得到薄膜样品的线性折射率为2.35,线性吸收系数为9.81×10~3cm^(-1),光学带隙宽度为3.60 eV。以脉宽300 fs,波长800 nm的钛蓝宝石脉冲激光为光源,利用单光束Z-scan技术测得薄膜样品的双光子吸收系数为100.31GW·cm^(-2),三阶非线性折射率为-1.02×10^(-2)GW·cm^(-2)。实验结果表明,所制备的BIT铁电薄膜具有大的非线性光学系数,适合应用于光子器件的制备。
The polycrystalline Bi4Ti3O12 （BIT） thin films with a-orientation were fabricated on the quartz substrates by a sol-gel technique. The fundamental optical constants （the bandgap, liner refractive index, and absorption coefficient） were determined as a function of light wavelength by optical transmittance measurements. By single-beam Z-scan experiments with femtosecond laser pulses at a wavelength of 800 nm, the third-order nonlinear refraction index and two-photon absorption coefficient were measured to be -1.02× 10^-2 GW· cm^-2 and 100.31 GW· cm^-2, respectively. The results indicate that the BIT candidate for applications in nonlinear photonic devices. film is a promising
出处
《现代应用物理》
2015年第2期125-130,共6页
Modern Applied Physics
基金
国家自然科学基金资助项目(11372266)
