K Noguchi

Publications (2)1.36 Total impact

• Article: Evidence of Electrical Spin Injection Into Silicon Using MgO Tunnel Barrier

  T. Sasaki, T. Oikawa, T. Suzuki, M. Shiraishi, Y. Suzuki, K. Noguchi
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  ABSTRACT: We demonstrate the evidence of electrical spin injection into silicon (Si) using the Fe/MgO tunnel barrier by the following two methods: 1) non-local (NL) four-terminal magnetoresistance (MR) scheme with their respective corresponding ferromagnetic (FM) electrode and 2) Hanle-type spin precession scheme. These results are compatible and in agreement with each other. The spin injection signals in the non-local scheme were observed up to 150 K, and the spin diffusion length (¿_N) was estimated to be 2.8 ¿m at 8 K. The experimental data completely matches every detail of the Hanle measurements equation, and spin lifetime (¿) was estimated to be 9.44 ns at 8 K. We will be able to discuss the physical properties of a pure spin current in silicon by this compelling data.
  IEEE Transactions on Magnetics 07/2010; · 1.36 Impact Factor
• Source

  Available from: arxiv.org

  Article: Temperature dependence of spin diffusion length in silicon by Hanle-type spin precession

  T Sasaki, T Oikawa, T Suzuki, M Shiraishi, Y Suzuki, K Noguchi
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  ABSTRACT: The Hanle-type spin precession method was carried out associated with non-local magnetoresistance measurement using a highly doped (5\times10^19) silicon channel. The spin diffusion length obtained by the Hanle-method is in good agreement with that by the gap dependence of non-local signals. We have evaluated the interface and bulk channel effects separately, and it was demonstrated that the major source of temperature dependence of non-local signals originates from the spin polarization reduction at interface between the tunnel barrier and silicon. Comment: 12 pages, 4 figure, To appear in Applied Physics Letters
  03/2010;