中国物理B ›› 2014, Vol. 23 ›› Issue (3): 34209-034209.doi: 10.1088/1674-1056/23/3/034209

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Intensity and composition-dependent sign reversal of non-linearity in TiO2/CeO2 nanocomposites

S. Divya, V. P. N. Nampoori, P. Radhakrishnan, A. Mujeeb   

  1. International School of Photonics, Cochin University of Science and Technology, Cochin, Kerala 682022, India
  • 收稿日期:2013-06-19 修回日期:2013-07-25 出版日期:2014-03-15 发布日期:2014-03-15
  • 基金资助:
    Project supported by the Department of Science and Technology (DST), Govt. of India.

Intensity and composition-dependent sign reversal of non-linearity in TiO2/CeO2 nanocomposites

S. Divya, V. P. N. Nampoori, P. Radhakrishnan, A. Mujeeb   

  1. International School of Photonics, Cochin University of Science and Technology, Cochin, Kerala 682022, India
  • Received:2013-06-19 Revised:2013-07-25 Online:2014-03-15 Published:2014-03-15
  • Contact: S. Divya E-mail:divyasasi7@gmail.com
  • Supported by:
    Project supported by the Department of Science and Technology (DST), Govt. of India.

摘要: CeO2/TiO2 composite nanoparticles with different Ce/Ti molar ratios have been successfully synthesized via sol–gel method. It was found that the band gap of the nanocomposite is tunable by varying Ce/Ti content. The nonlinear response of the sample was studied by using the nanosecond laser pulses from a Q switched Nd:Yag laser employing the Z-scan method. Open aperture Z-scan experiment revealed that with the increase in the CeO2 amount in the nanocomposite, the non-linearity of the composite increases, and it was assumed that this could be due to the modification of TiO2 dipole symmetry by the addition of CeO2. Closed aperture Z-scan experiment showed that when the CeO2 amount increases, positive nonlinear refraction decreases, and this could be attributed to the increase in the two photon absorption which subsequently suppresses the nonlinear refraction.

关键词: sol–, gel method, non-linearity, Z-scan experiment, reversesaturation absorption curve

Abstract: CeO2/TiO2 composite nanoparticles with different Ce/Ti molar ratios have been successfully synthesized via sol–gel method. It was found that the band gap of the nanocomposite is tunable by varying Ce/Ti content. The nonlinear response of the sample was studied by using the nanosecond laser pulses from a Q switched Nd:Yag laser employing the Z-scan method. Open aperture Z-scan experiment revealed that with the increase in the CeO2 amount in the nanocomposite, the non-linearity of the composite increases, and it was assumed that this could be due to the modification of TiO2 dipole symmetry by the addition of CeO2. Closed aperture Z-scan experiment showed that when the CeO2 amount increases, positive nonlinear refraction decreases, and this could be attributed to the increase in the two photon absorption which subsequently suppresses the nonlinear refraction.

Key words: sol–gel method, non-linearity, Z-scan experiment, reversesaturation absorption curve

中图分类号:  (Nonlinear optics)

  • 42.65.-k
42.70.Nq (Other nonlinear optical materials; photorefractive and semiconductor materials)