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arXiv · 1108.3145

Electrical spin injection and accumulation in CoFe/MgO/Ge contacts at room temperature

Kun-Rok Jeon·Byoung-Chul Min·Young-Hun Jo·Hun-Sung Lee·Il-Jae Shin·Chang-Yup Park·Seung-Young Park·Sung-Chul Shin
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Abstract

We first report the all-electrical spin injection and detection in CoFe/MgO/moderately doped n-Ge contact at room temperature (RT), employing threeterminal Hanle measurements. A sizable spin signal of ~170 k{\Omega} {\mu}m^2 has been observed at RT, and the analysis using a single-step tunneling model gives a spin lifetime of ~120 ps and a spin diffusion length of ~683 nm in Ge. The observed spin signal shows asymmetric bias and temperature dependences which are strongly related to the asymmetry of the tunneling process.

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Kun-Rok Jeon, Byoung-Chul Min, Young-Hun Jo, Hun-Sung Lee, Il-Jae Shin, Chang-Yup Park, Seung-Young Park, Sung-Chul Shin. 2011-08-16. Electrical spin injection and accumulation in CoFe/MgO/Ge contacts at room temperature. https://doi.org/10.1103/physrevb.84.165315

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