Shen Xudong, Zhou Long, Liu Zhehong, He Jincheng, Ye Xubin, Liu Guangxiu, Qin Shijun, Lu Dabiao, Zhang Jie, Sun Young, Long Youwen
Songshan Lake Materials Laboratory, Dongguan 523808, Guangdong, China.
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Inorg Chem. 2022 Sep 5;61(35):14030-14037. doi: 10.1021/acs.inorgchem.2c02022. Epub 2022 Aug 19.
Scheelite-type HoCrO was prepared by treating the ambient-pressure zircon-type precursor phase under 8 GPa and 700 K. A long-range antiferromagnetic phase transition is found to occur at ≈ 23 K due to the spin order of Ho and Cr magnetic ions. However, the antiferromagnetic ground state is sensitive to an external magnetic field and a moderate field of about 1.1 T can induce a metamagnetic transition, giving rise to the presence of a large magnetization up to 8.5 μ/f.u. at 2 K and 7 T. Considerable linear magnetoelectric effect is observed in the antiferromagnetic state, while the induced electric polarization experiences a sharp increase near the critical field of the metamagnetic transition. Ferromagnetism and ferroelectricity thus rarely coexist under higher magnetic fields in scheelite-type HoCrO. Moreover, a magnetic field also plays an important role in the longitudinal constriction of HoCrO, and a significant magnetostrictive effect with a value of up to 300 ppm is observed at 2 K and 9 T, which can be attributed to the strong anisotropy of the rare-earth Ho ion. Possible coupling between magnetoelectric and magnetoelastic effects is discussed.
通过在8吉帕斯卡和700开尔文的条件下处理常压锆石型前驱体相来制备白钨矿型HoCrO。由于Ho和Cr磁性离子的自旋有序，发现约在23开尔文时会发生长程反铁磁相变。然而，反铁磁基态对外部磁场敏感，约1.1特斯拉的中等磁场可诱导变磁转变，在2开尔文和7特斯拉时产生高达8.5μB/f.u.的大磁化强度。在反铁磁态中观察到显著的线性磁电效应，而感应电极化在变磁转变的临界场附近急剧增加。因此，在白钨矿型HoCrO中，铁磁性和铁电性在更高磁场下很少共存。此外，磁场在HoCrO的纵向收缩中也起着重要作用，在2开尔文和9特斯拉时观察到高达300 ppm的显著磁致伸缩效应，这可归因于稀土Ho离子的强各向异性。讨论了磁电和磁弹效应之间可能的耦合。
