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ecause it reduces the calculation of the spin transfer effect for non-collinear systems simply to the evaluation of spin currents
for P and AP orientations. Third, we demonstrate that the bias dependence for the spin current for the P (AP) configuration
has a linear (quadratic) bias dependence, whose origin lies on the symmetric (asymmetric) nature of the barrier. The interplay
of the spin currents for the P and AP configurations can lead to the rich behavior of the T
||
on bias shown in Figure 3(a). Last
but not least, as shown in Figure 3(b), we find that the bias dependence of T ⊥
is quadratic [11], independently of the
exchange splitting and that its value can be comparable to that of T
||
.
Figure. 3: Bias dependence of the spin transfer torque components parallel T
||
(a) and perpendicular T ⊥
(b) to the interface
as a function of the exchange-splitting, ∆.
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