Karpinsky Dmitry V, Fesenko Olena M, Silibin Maxim V, Dubkov Sergei V, Chaika Mykola, Yaremkevich Andrii, Lukowiak Anna, Gerasymchuk Yuri, Stręk Wiesław, Pakalniškis Andrius, Skaudzius Ramunas, Kareiva Aivaras, Fomichov Yevhen M, Shvartsman Vladimir V, Kalinin Sergei V, Morozovsky Nicholas V, Morozovska Anna N
Scientific-Practical Materials Research Centre of NAS of Belarus, 220072, Minsk, Belarus.
Institute of Physics, NAS of Ukraine, 46, pr. Nauky, 03028, Kyiv, Ukraine.
Sci Rep. 2019 Jul 18;9(1):10417. doi: 10.1038/s41598-019-46834-0.
We studied magnetostatic response of the BiLaFeO- KBr composites (BLFO-KBr) consisting of nanosized (≈100 nm) ferrite BiLaFeO (BLFO) conjugated with fine grinded ionic conducting KBr. When the fraction of KBr is rather small (less than 15 wt%) the magnetic response of the composite is very weak and similar to that observed for the BLFO (pure KBr matrix without BiLaFeO has no magnetic response as anticipated). However, when the fraction of KBr increases above 15%, the magnetic response of the composite changes substantially and the field dependence of magnetization reveals ferromagnetic-like hysteresis loop with a remanent magnetization about 0.14 emu/g and coercive field about 1.8 Tesla (at room temperature). Nothing similar to the ferromagnetic-like hysteresis loop can be observed in BiLaFeO ceramics with z ≤ 0.15, which magnetization quasi-linearly increases with magnetic field. Different physical mechanisms were considered to explain the unusual experimental results for BLFO-KBr nanocomposites, but only those among them, which are highly sensitive to the interaction of antiferromagnetic BiLaFeO with ionic conductor KBr, can be relevant.
我们研究了由纳米尺寸（约100纳米）的铁氧体BiLaFeO（BLFO）与细磨的离子导体KBr共轭组成的BiLaFeO - KBr复合材料（BLFO - KBr）的静磁响应。当KBr的含量相当低（小于15重量%）时，复合材料的磁响应非常微弱，与在BLFO中观察到的相似（如预期的那样，没有BiLaFeO的纯KBr基体没有磁响应）。然而，当KBr的含量增加到15%以上时，复合材料的磁响应发生显著变化，磁化强度与磁场的关系呈现出类似铁磁体的磁滞回线，剩余磁化强度约为0.14 emu/g，矫顽场约为1.8特斯拉（在室温下）。在z≤0.15的BiLaFeO陶瓷中未观察到类似铁磁体的磁滞回线，其磁化强度随磁场呈准线性增加。人们考虑了不同的物理机制来解释BLFO - KBr纳米复合材料异常的实验结果，但其中只有那些对反铁磁体BiLaFeO与离子导体KBr之间的相互作用高度敏感的机制才可能相关。
