Ni_(50)Mn_(37)In_(13)磁驱动形状记忆合金薄膜中的交换偏置

Exchange Bias in Ni_(50)Mn_(37)In_(13) Magnetic Shape Memory Alloy Thin Films

研究了磁场冷却前后Ni50Mn37In13磁驱动形状记忆合金薄膜在低温下的磁学行为。结果表明:磁场冷却后的Ni50Mn37In13薄膜在10 K温度下表现出一定的交换偏置效应。在特征温度Tf以下,零场冷却状态下的Ni50Mn37In13合金处于超自旋玻璃态,而经磁场冷却后发生了从自旋玻璃态向磁有序的超铁磁结构的变化。超铁磁结构中的超铁磁团簇与反铁磁基体构成了铁磁/反铁磁耦合,从而导致了交换偏置的产生。

The magnetic behaviors of the magnetic-field cooled NisoMn37In13 film at low temperature was investigated. The results show that below the characteristic temperature Tf, the alloy presents a super spin glass （SSG） state when cooled in the absence of a magnetic field; however, it will transform to the super ferromagnetic （SFM） structure after magnetic field cooling. The SFM clusters in the SFM structure are coupled with the antiferromagnetic matrix, resulting in the exchange bias.