Electrically controllable spin polarization in collinear antiferromagnetic junctions

Antiferromagnetic spintronics is a rapidly growing subfield of spintronics in condensed-matter physics and information technology. Electrical current in collinear antiferromagnetic materials is typically spin unpolarized, limiting the realization of antiferromagnetic spintronics effects. Here we study the transport in the collinear antiferromagnetic junctions by applying a transverse electric field E ( y ) to the antiferromagnets (AFs). The band structures of the collinear AFs may become spin-polarized when the combined time reversal and lattice translation symmetry is broken by E ( y ). The separation between spin-up and spin-down bands is controlled by E ( y ). Full spin polarization originating from spin-polarized states near the band gap's edges is observed at high exchange energy. In particular, as E ( y ) increases, the region capable of generating high spin polarization broadens due to the increased separation between spin-up and spin-down bands. The amplitude and sign of spin polarization can be controlled by E ( y ). These characteristics indicate that collinear AF materials are ideal for future spintronics applications.