Processing and properties of pure antiferromagnetic h-YMnO3

Abstract

Yttrium manganite (YMnO3) is widely investigated multiferroic material with potential use in many technological applications. In this paper, we report on the preparation and characterization of multiferroic hexagonal YMnO3 ceramics obtained by chemical synthesis route. Precursor powders were prepared by the polymerizable complex method from citrate precursors. After calcination at 900?C the powders contained mixture of Y-Mn-O phases which were further sintered at different temperatures. XRD analysis revealed that sintering at 1400?C resulted in the formation of pure hexagonal YMnO3. Density of the obtained ceramics was 96%TD. The ceramic samples proved to have multiferroic properties - they are antiferromagnetic below 42K with linear dependence of magnetization as a function of applied magnetic field. The ferroelectric measurements performed at room temperature showed remanent polarization of 0.21 ?C/cm2 and the coercive field of 6.0 kV/cm for the YMnO3 sample sintered at 1400?C. The magnetization curves measured at 2 and 5 K for the powder samples calcined at 900?C and ceramic samples sintered at 1300?C exhibited a hysteresis loop due to a small concentration of Mn3O4 in the samples.