Spin Dephasing in Drift-Dominated Semiconductor Spintronics Devices

A spin transport model is employed to study the effects of spin dephasing induced by diffusion-driven transit-time uncertainty through semiconductor spintronic devices where drift is the dominant transport mechanism. It is found that in the ohmic regime, dephasing is independent of transit length, and determined primarily by voltage drop across the spin transport region. The effects of voltage and temperature predicted by the model are compared to experimental results from a 350-micron-thick silicon spin-transport device using derived mathematical expressions of spin dephasing.