@article{WU2021, 
author = {Xingxing WU and Shouyu WANG and Winnie WONG-NG and Qiang GU and Yao JIANG and Chao WANG and Shuang MA and Weifang LIU},
title = {Novel optical properties and induced magnetic moments in Ru-doped hybrid improper ferroelectric Ca3Ti2O7},
year = {2021},
journal = {Journal of Advanced Ceramics},
volume = {10},
number = {1},
pages = {120-128},
keywords = {oxides, electronic materials, optical properties, X-ray diffraction, defects, lectronic structure, ferroelectricity},
url = {https://www.sciopen.com/article/10.1007/s40145-020-0425-2},
doi = {10.1007/s40145-020-0425-2},
abstract = {Hybrid improper ferroelectric Ca3Ti2O7 and Ca3Ti1.9Ru0.1O7 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.}
}