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arXiv · 1105.1012

Spin accumulation created electrically in an n-type germanium channel using Schottky tunnel contacts

K. Kasahara·Y. Baba·K. Yamane·Y. Ando·S. Yamada·Y. Hoshi·K. Sawano·M. Miyao·K. Hamaya
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Abstract

Using high-quality Fe$_{3}$Si/$n^{+}$-Ge Schottky-tunnel-barrier contacts, we study spin accumulation in an $n$-type germanium ($n$-Ge) channel. In the three- or two-terminal voltage measurements with low bias current conditions at 50 K, Hanle-effect signals are clearly detected only at a forward-biased contact. These are reliable evidence for electrical detection of the spin accumulation created in the $n$-Ge channel. The estimated spin lifetime in $n$-Ge at 50 K is one order of magnitude shorter than those in $n$-Si reported recently. The magnitude of the spin signals cannot be explained by the commonly used spin diffusion model. We discuss a possible origin of the difference between experimental data and theoretical values.

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K. Kasahara, Y. Baba, K. Yamane, Y. Ando, S. Yamada, Y. Hoshi, K. Sawano, M. Miyao, K. Hamaya. 2011-10-18. Spin accumulation created electrically in an n-type germanium channel using Schottky tunnel contacts. https://doi.org/10.1063/1.3670985

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