Electric dipoles via Cr~(3+)(d~3) ion off-center displacement in perovskite DyCrO_3

摘要

We report on electric dipoles induced by magnetic ion Cr~(3+)(d~3) off-center displacement with potential strong magnetoelectric coupling in simple perovskite DyCrO_3 crystals. DyCrO_3 was found to show quantum paraelectric behavior and the existence of electrical dipoles, as revealed by the dielectric, Raman scattering, and x-ray absorption near-edge structure spectra experiments. The anomalous lattice volume decreasing rate at low temperatures might play an important role in the Cr~(3+) ion displacement induced polar instability in DyCrO_3 as predicted by previous theoretical calculations. Our results on DyCrO_3 provide important experimental evidence for non-d~0 transition-metal ion displacement induced electric dipoles, and they may lead to the exploration of multiferroics in a wider range of materials, especially magnetic perovskites.