Separating spins by dwell time of electrons across parallel double δ-magnetic-barrier nanostructure applied by bias

The dwell time and spin polarization (SP) of electrons tunneling through a parallel double δ-magnetic-barrier nanostructure in the presence of a bias voltage is studied theoretically in this work. This nanostructure can be constructed by patterning two asymmetric ferromagnetic stripes on the top and bottom of InAs/Al_xIn_1-xAs heterostructure, respectively. An evident SP effect remains after a bias voltage is applied to the nanostructure. Moreover, both magnitude and sign of spin-polarized dwell time can be manipulated by properly changing the bias voltage, which may result in an electrically-tunable temporal spin splitter for spintronics device applications.