Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK.
J Am Chem Soc. 2012 Feb 29;134(8):3737-47. doi: 10.1021/ja208395z. Epub 2012 Feb 15.
Combining long-range magnetic order with polarity in the same structure is a prerequisite for the design of (magnetoelectric) multiferroic materials. There are now several demonstrated strategies to achieve this goal, but retaining magnetic order above room temperature remains a difficult target. Iron oxides in the +3 oxidation state have high magnetic ordering temperatures due to the size of the coupled moments. Here we prepare and characterize ScFeO(3) (SFO), which under pressure and in strain-stabilized thin films adopts a polar variant of the corundum structure, one of the archetypal binary oxide structures. Polar corundum ScFeO(3) has a weak ferromagnetic ground state below 356 K-this is in contrast to the purely antiferromagnetic ground state adopted by the well-studied ferroelectric BiFeO(3).
在同一结构中结合长程磁有序和极性是设计（磁电）多铁材料的前提。目前已经有几种方法可以实现这一目标，但在室温以上保持磁有序仍然是一个难以达到的目标。由于耦合矩的大小，+3 价氧化态的铁氧化物具有较高的磁有序温度。在这里，我们制备并表征了 ScFeO(3)（SFO），它在压力和应变稳定的薄膜中采用了刚玉结构的一种极性变体，这是典型的二元氧化物结构之一。极性刚玉 ScFeO(3)在 356 K 以下具有弱铁磁基态——这与经过充分研究的铁电 BiFeO(3)所采用的纯反铁磁基态形成了对比。
