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arXiv · 1207.1154

Evidence for the Presence of Spin Accumulation in Localized States at Ferromagnet-Silicon Interfaces

Y. Ando·S. Yamada·K. Kasahara·K. Masaki·K. Sawano·M. Miyao·K. Hamaya
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Abstract

We experimentally show evidence for the presence of spin accumulation in localized states at ferromagnet-silicon interfaces, detected by electrical Hanle effect measurements in CoFe/$n^{+}$-Si/$n$-Si lateral devices. By controlling the measurement temperature, we can clearly observe marked changes in the spin-accumulation signals at low temperatures, at which the electron transport across the interface changes from the direct tunneling to the two-step one via the localized states. We discuss in detail the difference in the spin accumulation between in the Si channel and in the localized states.

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Y. Ando, S. Yamada, K. Kasahara, K. Masaki, K. Sawano, M. Miyao, K. Hamaya. 2012-07-05. Evidence for the Presence of Spin Accumulation in Localized States at Ferromagnet-Silicon Interfaces. https://arxiv.org/abs/1207.1154

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