Creation of synthetic Rashba field in silicon by gate electric field

Abstract

Creation of the synthetic Rashba field in a Si channel of Si spin MOSFET is introduced and discussed. The Rashba field is attributed to the local electric field at the Si/SiO₂ interface and is tuneable by a gate electric field. An effective magnetic field due to the Rashba field gives rise to spin lifetime anisotropy in a Si channel, which is detected by the oblique Hanle effect. It is also found that the Rashba field is built-in even at the gate voltage of 0 V. The magnitude of the spin splitting energy is estimated to be 0.6 μeV, which is comparable to that in strained GaAs.