Modulation of spin-charge conversion in silicon

Abstract

Silicon (Si) is an important material for the application of spintronics because its spin lifetime is relatively long compared to those of metals, and it is the well-studied semiconductor in term of its electronic properties. However, as a potential spintronic material, the complete knowledge about the spintronic properties of Si is still not established yet. In this work, the technique of ferromagnetic resonance driven spin pumping is adopted to accurately determine several critical parameters, including the spin lifetime (τs), the spin diffusion length (λs), and the spin Hall angle (θISHE) of Si. By changing the type (n- and p-type) of carrier and the carrier concentration (1 × 1013 to 1.7 × 1019 cm−3), a correlation between λs and θISHE is found, suggesting an effective route to tune the efficiency of spin-charge conversion in Si.