标题： 与多晶La_{0.88}Sr_{0.12}CoO_3中隧穿磁阻相关的交换偏置效应 显示英文标题

标题： Exchange bias effect involved with tunneling magnetoresistance in polycrystalline La_{0.88}Sr_{0.12}CoO_3

摘要： 我们报告了多晶La_{0.88}Sr_{0.12}CoO_3中的交换偏置（EB）效应以及隧道磁阻（MR）效应。 类似于磁场（H）轴上的磁滞回线偏移，在样品在静态磁场中冷却时，MR-H曲线中明显观察到偏移。 训练效应（TE）是EB效应的一个显著表现，它描述了在特定温度下样品依次场循环时EB效应的减小。 我们在MR-H曲线的偏移中观察到了TE，这可以通过自旋构型弛豫模型来解释。 在自旋冻结温度以下，电阻率的温度和时间依赖性中观察到了强烈的场冷（FC）效应。 在FC模式下测量的异常MR结果被解释为短程铁磁团簇与自旋玻璃基质之间的晶内界面效应，导致了EB效应。 在双层或多层薄膜中已经观察到了MR中的EB效应，但在多晶化合物中尚未见过。 涉及隧穿MR和半导体输运特性的EB效应归因于晶内本征纳米结构，这在自旋电子学应用中具有前景。 显示英文摘要

摘要： We report the exchange bias (EB) effect along with tunneling magnetoresistance (MR) in polycrystalline La_{0.88}Sr_{0.12}CoO_3. Analogous to the shift in the magnetic hysteresis loop along the field (H)-axis a shift is clearly observed in the MR-H curve when the sample is cooled in a static magnetic field. Training effect (TE) is a significant manifestation of EB effect which describes the decrease of EB effect when sample is successively field-cycled at a particular temperature. We observe TE in the shift of the MR-H curve which could be interpreted by the spin configurational relaxation model. A strong field-cooled (FC) effect in the temperature as well as time dependence of resistivity is observed below spin freezing temperature. The unusual MR results measured in FC mode are interpreted in terms of intragranular interface effect between short range ferromagnetic clusters and spin-glass matrix giving rise to the EB effect. EB effect in MR has been observed in bilayer or multilayer films which has not yet seen in a polycrystalline compound. EB effect involved with tunneling MR and semiconducting transport property attributed to the intragranular intrinsic nanostructure is promising for the spintronic applications.