Direct evidence of electronic ferroelectricity in YbFe₂O₄ using neutron diffraction and nonlinear spectroscopy.

ABSTRACT: We report the first observation of room temperature spontaneous electric polarization in an electronic ferroelectric material, a YbFe₂O₄ single crystal. The observation was based on second harmonic generation (SHG), a nonlinear optical process. Tensor analysis of the SHG signal revealed that this material has a polar charge superstructure with Cm symmetry. This result settles the long-term discussion on the uncertainty about electronic ferroelectric properties, including the charge order structure. We present a complete picture of the polar charge ordering of this material via consistent results from two different characterization methods. The SHG signal shows the same temperature dependence as the superlattice signal observed in neutron diffraction experiments. These

SUBMITTER: Fujiwara K 

PROVIDER: S-EPMC7896071 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature