Novel optical properties and induced magnetic moments in Ru-doped hybrid improper ferroelectric Ca3Ti2O7


Hybrid improper ferroelectric Ca3Ti2O7 and Ca3Ti19Ru0.1O7 ceramics were successfully synthesized by conventional solid-state reaction method. Two strongest diffraction peaks located around 2θ = 33° shifted towards the lower angle region with Ru substitution, reflecting structure variation. Grain growth and higher oxygen vacancy concentration after doping resulted in a reduction in the coercive field about 20 kV/cm. Optical bandgap estimated by UV-vis diffuse reflectance (DR) spectrum and X-ray photoelectron spectroscopy (XPS) valence band spectra showed a decreasing trend due to the existence of impurity energy level upon Ru doping, which was consistent with the results of first-principles calculations. The origin of the unexpected induced magnetic moments in Ru-dope Ca3Ti2O7 is also discussed.


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This work was funded by the National Natural Science Foundation of China (51572193), and the Natural Science Foundation of Tianjin (20JCZDJC00210).

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Correspondence to Shouyu Wang or Weifang Liu.

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Wu, X., Wang, S., Wong-Ng, W. et al. Novel optical properties and induced magnetic moments in Ru-doped hybrid improper ferroelectric Ca3Ti2O7. J Adv Ceram 10, 120–128 (2021).

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  • oxides
  • electronic materials
  • optical properties
  • X-ray diffraction
  • defects
  • lectronic structure
  • ferroelectricity