Study on New material with Multiferroic Properties by Means of Containerless Solidification

到目前为止，我们已经报道，在LuFeO_3中，无容器处理可以促进具有多铁性的亚稳六方相(h-LuFeO_3)的形成。然而，h-LuFeO_3的磁性不是铁磁性而是反铁磁性，这阻碍了该材料的实用化。为了解决这个问题，我们研究了适合于纳米级复合材料的化学成分和加工条件，因为形成这两种相的纳米级混合物是实现多铁性的潜在方法之一。结果表明，Lu(FexMn1-x)2+yO4+z是一种很有潜力的材料，因为少量Fe3+对Mn2+的取代稳定了亚稳态的h-LuFeO_3，并抑制了平衡正交相(o-LuFeO_3)的析出。

Until now, we have reported that in LuFeO3 the containerless processing can facilitate the metastable hexagonal phase(h-LuFeO3) with multiferroic properties to be formed. However, the magnetic properties of h-LuFeO3, which are not ferromagnetic but antiferromagnetic, prevent the material to be used practically. In order to solve this problem, we examined the chemical composition and the processing condition which are suited for a nano-scaled composite, because the forming of a nano-scaled mixture of these two phases is one of the potential methods for the multiferroic properties. As a result, we reached the conclusion that Lu(FexMn1-x) 2+yO4+z is one of the potential materials, because the substitution of a small fraction of Fe3+to Mn2+stabilizes the metastable h-LuFeO3, and suppresses the precipitation of the equilibrium orthorhombic phase(o-LuFeO3).