We study the in--plane spin--transfer torque in magnetic tunnel junctions for different band fillings and exchange splittings. The range of biases over which the in--plane torque is linear depends strongly on these parameters. If the ferromagnetic layer has a half--metallic behavior with respect to the tunneling states the linear range in the bias dependence of the in--plane torque is significantly larger that if the behavior is metallic. For parameters that reproduce the important features of the Fe band structure, the results are in agreement with experimental data as well as with ab initio calculations.
Citation: Journal of Applied Physics
Pub Type: Journals
MRAM, tunnel junctions, electronic structure, spin transfer torque, spintronics, TMR