Interfacial Ferromagnetism and Exchange Bias in CaRuO3/CaMnO3 Superlattices
Interfacial Ferromagnetism and Exchange Bias in CaRuO3/CaMnO3 Superlattices
复制标题
CaRuO3/CaMnO3 超晶格中的界面铁磁性和交换偏置
DOI：
10.1103/physrevlett.109.197202
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发表时间：
2012-11-07
影响因子：
8.6
通讯作者：
Suzuki, Y.
中科院分区：
文献类型：
--
作者：
He, C.;Grutter, A. J.;Suzuki, Y.
We have found ferromagnetism in epitaxially grown superlattices of CaRuO3/CaMnO3 that arises in one unit cell at the interface. Scanning transmission electron microscopy and electron energy loss spectroscopy indicate that the difference in magnitude of the Mn valence states between the center of the CaMnO3 layer and the interface region is consistent with double exchange interaction among the Mn ions at the interface. Polarized neutron reflectivity and the CaMnO3 thickness dependence of the exchange bias field together indicate that the interfacial ferromagnetism is only limited to one unit cell of CaMnO3 at each interface. The interfacial moment alternates between the 1 mu(B)/interface Mn ion for even CaMnO3 layers and the 0.5 mu(B)/interface Mn ion for odd CaMnO3 layers. This modulation, combined with the exchange bias, suggests the presence of a modulating interlayer coupling between neighboring ferromagnetic interfaces via the antiferromagnetic CaMnO3 layers.
