Interfacial spin glass state and exchange bias in manganite bilayers with competing magnetic orders
Interfacial spin glass state and exchange bias in manganite bilayers with competing magnetic orders
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DOI：
10.1103/physrevb.87.054428
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发表时间：
2013-02-21
影响因子：
3.7
通讯作者：
Wu, T.
中科院分区：
文献类型：
--
作者：
Ding, J. F.;Lebedev, O. I.;Wu, T.
研究了由G型反铁磁(AFM)SrMnO_3和双交换铁磁(FM)La_(0.7)Sr_(0.3)MnO_3组成的锰氧化物双层膜的磁性。在La0.7Sr0.3MnO_3/SrMnO_3界面上观察到磁序竞争和自旋受挫导致的自旋玻璃态。不可逆温度与冷却磁场的关系符合Almeida-Thouless曲线。尽管理想的G型原子力显微镜SrMnO_3具有补偿的自旋组态，但双层膜在自旋玻璃冻结温度以下表现出交换偏置，远低于SMO的Neel温度，表明交换偏置与自旋玻璃态密切相关。结果表明，AFM超交换和FM双交换相互作用的竞争产生的自旋受挫能在La0.7Sr0.3MnO_3/SrMnO_3界面引起强烈的磁各向异性。DOI：10.1103/PhysRevB.87.054428
The magnetic properties of manganite bilayers composed of G-type antiferromagnetic (AFM) SrMnO3 and double-exchange ferromagnetic (FM) La0.7Sr0.3MnO3 are studied. A spin-glass state is observed as a result of competing magnetic orders and spin frustration at the La0.7Sr0.3MnO3/SrMnO3 interface. The dependence of the irreversible temperature on the cooling magnetic field follows the Almeida-Thouless line. Although an ideal G-type AFM SrMnO3 is featured with a compensated spin configuration, the bilayers exhibit exchange bias below the spin glass freezing temperature, which is much lower than the Neel temperature of SMO, indicating that the exchange bias is strongly correlated with the spin glass state. The results indicate that the spin frustration that originates from the competition between the AFM super-exchange and the FM double-exchange interactions can induce a strong magnetic anisotropy at the La0.7Sr0.3MnO3/SrMnO3 interface. DOI: 10.1103/PhysRevB.87.054428