论文标题
具有非共线化磁化的自旋阀中的非平衡动力学
Nonequilibrium dynamics in a spin valve with noncollinear magnetization
论文作者
论文摘要
我们利用运动方法的杂化量子经典方程来研究偏置电压下自旋阀中的自旋动力学和自旋转移扭矩。我们表明，局部经典磁矩与传导电子之间的相互作用会引起磁层之间复杂的有效交换耦合。这会导致层的磁化量减少，即使在平衡状态下也是如此。引入有限的偏置电压会触发旋转电流和相关的自旋转移扭矩，从而进一步倾斜磁性并控制自旋动力学的松弛过程。分析应用偏置电压的不同场景，我们表明对称和不对称的电压下降会导致自旋动力学的放松时间，这些旋转动力学在可比电荷电流下通过几个数量级不同。在这两种情况下，我们都会观察到共振的特征，每当铅的化学势与自旋 - 阀电子状态的密度匹配的最大值时，弛豫就会增强。
We utilize a hybrid quantum-classical equation of motion approach to investigate the spin dynamics and spin-transfer torque in a spin valve under bias voltage. We show that the interplay between localized classical magnetic moments and conduction electrons induces a complex effective exchange coupling between the magnetic layers. This leads to a declination of magnetizations from layers anisotropy axes even in equilibrium. Introducing a finite bias voltage triggers spin currents and related spin-transfer torques which further tilt the magnetizations and govern the relaxation processes of the spin dynamics. Analyzing different scenarios of the applied bias voltage, we show that symmetric and asymmetric voltage drops can lead to relaxation times of the spin dynamics that differ by several orders of magnitude at comparable charge currents. In both cases we observe resonant features, where the relaxation is boosted whenever the chemical potential of the leads matches the maxima in the density of the states of the spin-valve electrons.
