  Current flowing is studied in magnetic junctions consisting of a
ferromagnetic metal (FM), antiferromagnetic conductor (AFM) and a nonmagnetic
metal closing the electric circuit. The FM layer with high anisotropy and
pinned spins of the magnetic atoms in the lattice acts as a spin injector
relative to the AFM layer. To obtain resulting magnetization in the AFM layer,
magnetic field is applied, which may be varied to control the magnetization.
The spin-polarized current from the FM layer creates a torque and makes it
possible to switch the magnetization. A possibility is shown to lower the
threshold current density by the orders of magnitude by means of the magnetic
field.
