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تسجيل مستخدم جديدPure spin current transport in a SiGe alloy
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Using four-terminal nonlocal magnetoresistance measurements in lateral spin-valve devices with Si$_{rm 0.1}$Ge$_{rm 0.9}$, we study pure spin current transport in a degenerate SiGe alloy ($n sim$ 5.0 $times$ 10$^{18}$ cm$^{-3}$). Clear nonlocal spin-valve signals and Hanle-effect curves, indicating generation, manipulation, and detection of pure spin currents, are observed. The spin diffusion length and spin lifetime of the Si$_{rm 0.1}$Ge$_{rm 0.9}$ layer at low temperatures are reliably estimated to be $sim$ 0.5 $mu$m and $sim$ 0.2 ns, respectively. This study demonstrates the possibility of exploring physics and developing spintronic applications using SiGe alloys.
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Matthias Althammer
, Joynarayan Mukherjee
, Stephan Geprags andn Sebastian T. B. Goennenwein
2016
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