Variation of Spin Lifetime with Spin Injection Orientation in Strained Thin Silicon Films

Spintronics attracts at present much interest because of the potential to build novel spin-based devices which are superior to charge-based microelectronic elements. Silicon, the main element of microelectronics, is promising for spin-driven applications. Understanding the peculiarities of the subband structure and details of spin propagation in thin silicon films in the presence of the spinorbit interaction is under scrutiny. We show that shear strain has a strong influence in modifying the subband structure and thus can dramatically boost both of the surface roughness and electronphonon interaction limited spin lifetime in an ultra-thin silicon-oninsulator-based transistor. We also report that a change in the spin injection direction has an impact on the spin lifetime.