Enhanced ferromagnetic interactions in chromium (III) doped YMnO₃

Recently the substantial attention has been paid to the hexagonal rare earth manganites (RMnO₃) owing their multiferroic character i.e. the coexistence of ferroelectric (FE) and magnetic spin orders. The hexagonal RMnO₃ forms a geometrically frustrated magnetic state due to the incomplete antiferromagnetic (AFM) coupling between neighboring Mn ions in the triangular lattice. Both of the reported compounds with compositions YMn_1-xCr_xO₃ (x = 0.1 and 0.2) are synthesized by using the conventional solid state reaction method and their magnetic properties are analyzed vigilantly. The XRD pattern reveals the hexagonal structure of the reported compounds with space group P6₃cm (25-1079). The temperature dependence of combined FC and ZFC magnetic moment for YMn_0.9Cr_0.1O₃ and YMn_0.8Cr_0.2O₃ compounds within the temperature ranges from 2K to 120K are shown. The in-depth analysis of the magnetic measurements reveals the enhancement in the ferromagnetic character with Cr doping in YMnO₃ compounds. The observed enhancement in the ferromagnetism is found to be due to the increased double exchange interactions among the Cr³⁺ and Mn³⁺ ions with Cr doping. (author)