Observation of strongly enhanced inverse spin Hall voltage in Fe 3 Si/GaAs structures
Journal
Applied Physics Letters
Journal Volume
105
Journal Issue
15
Date Issued
2014
Author(s)
Abstract
We performed spin pumping experiment on high quality, epitaxial Fe3Si/GaAs structures grown by molecular beam epitaxy. By tailoring the thickness and doping (n, p) level of the conducting GaAs epi-layer, thermal heating common of ferromagnetic metal/semiconductor heterostructure was removed effectively. A large inverse spin Hall Effect (ISHE) voltage up to 49.2 μV was observed for Fe3Si/p-GaAs. Smaller ISHE voltage (VISHE) by a factor of ∼0.4 was obtained for Fe3Si/n-GaAs, as scaled with its resistivity. By taking into account of the "self-induced" ISHE apparently observed in our samples, the minimum value of spin Hall angle θISHE for n-GaAs and p-GaAs was estimated to be 1.9 × 10-4 and 2.8 × 10-5, respectively.
Type
journal article