Spin injection and transport in Ge/SiGe multilayer structures on Si

Ge/SiGe heterostructures are promising candidates for Si-compatible optoelectronic and spintronic devices because Ge offers strong optical functionality on Si. In this study, we explore spin injection and transport in a Ge/SiGe multilayer channel grown on Ge/Si(111) substrates. Clear nonlocal and local spin-valve signals are observed up to room temperature, and the spin diffusion length λ s is extracted, enabling evaluation of the spin-relaxation time τ s . These results suggest that the present multilayer structure enables the use of SiGe spin transport properties without compromising the optical functionality of Ge.