Sharma Mohit K, Basu Tathamay, Mukherjee K, Sampathkumaran E V
School of Basic Sciences, Indian Institute of Technology Mandi, Mandi 175005, Himachal Pradesh, India.
J Phys Condens Matter. 2016 Oct 26;28(42):426003. doi: 10.1088/0953-8984/28/42/426003. Epub 2016 Sep 2.
We report the results of our investigations on the influence of partial substitution of Er and Gd for Dy on the magnetic and magnetoelectric properties of DyFe0.5Cr0.5O3, which is known to be a multiferroic system. Magnetic susceptibility and heat capacity data, apart from confirming the occurrence of magnetic transitions at ~121 and 13 K in DyFe0.5Cr0.5O3, bring out that the lower transition temperature only is suppressed by rare-earth substitution. Multiferroic behavior is found to persist in Dy0.4Ln0.6Fe0.5Cr0.5O3 (Ln = Er and Gd). There is an evidence for magnetoelectric coupling in all these materials with qualitative differences in its behavior as the temperature is changed across these two transitions. Remnant electric polarization is observed for all the compounds. The most notable observation is that electric polarization is seen to get enhanced as a result of rare-earth substitution with respect to that in DyFe0.5Cr0.5O3. Interestingly, a similar trend is seen in the magnetocaloric effect, consistent with the existence of magnetoelectric coupling. The results thus provide evidence for the tuning of magnetoelectric coupling by rare-earth substitution in this family of oxides.
我们报告了关于用铒（Er）和钆（Gd）部分替代镝（Dy）对DyFe0.5Cr0.5O3磁电性能影响的研究结果，DyFe0.5Cr0.5O3是一个已知的多铁性体系。除了证实DyFe0.5Cr0.5O3中在约121K和13K处发生磁转变外，磁化率和热容量数据还表明，只有较低的转变温度会受到稀土元素替代的抑制。研究发现，多铁性行为在Dy0.4Ln0.6Fe0.5Cr0.5O3（Ln = Er和Gd）中持续存在。所有这些材料都存在磁电耦合的证据，并且随着温度在这两个转变过程中变化，其行为存在定性差异。所有化合物都观察到了剩余极化。最值得注意的观察结果是，与DyFe0.5Cr0.5O3相比，稀土元素替代导致极化增强。有趣的是，磁热效应也呈现出类似趋势，这与磁电耦合的存在相一致。因此，这些结果为通过稀土元素替代来调节该氧化物家族中的磁电耦合提供了证据。
