Electronic structure of Ru and Mn in new potential multiferroic materials Ca3Mn2-xRuxO7 (x<=0.5)

Multiferroic materials, by virtue of the coexisting ferro-electric/magnetic orderings, are very attractive for microelectronic applications (e.g. energy-efficient logic memory devices). Currently, there is a growing interest in hybrid improper ferroelectrics such as layered perovskite Ca3Mn2O7 for the realization of room temperature multiferroicity. We have succeeded in obtaining single-phase Ca3Mn2-xRuxO7 samples with x up to 0.5, which show enhanced ferromagnetism compared to the parent compound. We propose to investigate the electronic structure (oxidation state, local distortion and spin state) of Ru and Mn by combining Ru L3 edge HERFD-XANES in the recently commissioned TEXS spectrometer with Mn K edge HERFD-XANES and Kbeta XES at ID26 beamline. The results will provide new understanding about the microscopic origin of ferromagnetism and ferroelectricity in these new compounds, which is crucial to enable a rational design of materials with exploitable multiferroic properties.