Possibility of increasing the efficiency of spin injection by current in magnetic junctions

Effect of current on magnetization oscillations in the ferromagnet-antiferromagnet junction

“…In addition, the ferromagnetic resonance frequency is quite low in this case. In view of the above mentioned difficulties, other methods were also proposed for reducing the threshold (e.g., using a high spin injection level [8] or joint action of the external magnetic field and polar ization current [9,10]). The employment of ferromag net-antiferromagnet junctions, in which the ferro magnet (FM) serves as an injector of spin polarized electrons, and the antiferromagnetic (AFM) layer in an external magnetic field perpendicular to the easy axis may have a low magnetization because the mag netic sublattices are "canted," which facilitates the lowering of the threshold [11].…”

Current-induced exchange switching magnetic junctions with cubic anisotropy of the free layer

“…The relative contribution of the mechanisms indicated depends on the layer parameters and the applied magnetic field. Earlier, the conditions were formulated [12,13,5] under which the injection mechanism plays the main role (see below for details). In this work, special attention is paid to the latter.…”

Lower current-driven exchange switching threshold in noncollinear magnetic junctions under high spin injection

“…An alternative way proposed in Ref. 4 is founded on such a choice of the pinned, free, and nonmagnetic layers that provides high spin injection from the pinned layer to the free one and blocking injection from the free layer to nonmagnetic one, so that high nonequilibrium spin polarization takes place in the free layer and the threshold current can be lowered by one to two orders of magnitude. Recently, it was shown 5, 6 that the impact of radio‐frequency current on the direct current‐driven switching dynamics in spin valves can lower considerably the switching threshold.…”

“…We show that such a situation is not universal, so that the switching threshold can be lower under noncollinear configuration in comparison with collinear one. Note that the effect in question can work in cooperation with the other 3, 4 methods of lowering the switching threshold. Moreover, further decreasing of the threshold may be achieved under the influence of an external magnetic field.…”

“…One of the most important problems is lowering the current density threshold corresponding to instability of the initial magnetic configuration and switching it to another one with different resistance. Various ways have been proposed to solve the problem, namely, using magnetic semiconductors with their lower saturation magnetizations [2], choosing the layer materials with proper spin resistances [3], and so on. In this note, we consider an additional possibility of lowering the threshold current density corresponding to instability and switching the magnetic configuration of the magnetic junction.…”