Structural, optical and multiferroic properties of pure and Dy modified YMnO3

A soft chemical co-precipitation method has been proposed for the synthesis of YMnO3 (YMO) and Dy-modified YMO (YDMO) powders. X-ray diffraction (XRD) pattern confirms the existence of single phase in YMO and YDMO powders with hexagonal structure belonging to P6(3) cm space group. The crystallite sizes deduced from XRD line width analysis is found to be within 38-28 nm. A broadening and shifting of Raman-active phonon modes towards lower frequencies have been observed in YDMO in comparison to YMO. Dielectric measurements showed a gradual increase of dielectric constant values with increasing of Dy concentration. From the temperature dependent dielectric measurements, both YMO and YDMO samples showed a dielectric anomaly around 340 A degrees C signifies the relaxation of doubly ionized oxygen vacancies. Magnetization versus magnetic field (M-H) curves of YMO and YDMO measured at room temperature suggests a paramagnetic behaviour. Compared to YMO, leakage current densities in YDMO samples are found to be improved by an order and more.