Experimental realization of a silicon spin field-effect transistor

A longitudinal electric field is used to control the transit time (through an undoped silicon vertical channel) of spin-polarized electrons precessing in a perpendicular magnetic field. Since an applied voltage determines the final spin direction at the spin detector and hence the output collector current, this comprises a spin field-effect transistor. An improved hot-electron spin injector providing ≈ 115 % magnetocurrent, corresponding to at least ≈ 37 % electron current spin polarization after transport through 10 μ m undoped single-crystal silicon, is used for maximum current modulation.