Barrier-dependent switching effect in spin field-effect transistors

We investigate the barrier-dependent conductance properties in spin field-effect transistors (SFET) by taking into account the presence of external magnetic field. It is shown that the conductance of the SFET has high peaks while the potential barriers strength varies. These peaks become more and more pronounced with the increasing potential barriers strength. Numerical results indicate that switching on or off can be realized in SFET by tuning the potential barriers strength. We also show that the conductance of the SFET exhibits an excellent double switching effect as the strength of the spin–orbit coupling varies. It is found that the application of external magnetic field will enhance the switching effect in SFET. The results may be of relevance to the implementation of SFET devices.