Hayashi Masamitsu, Thomas Luc, Rettner Charles, Moriya Rai, Bazaliy Yaroslaw B, Parkin Stuart S P
IBM Almaden Research Center, San Jose, California, USA.
Phys Rev Lett. 2007 Jan 19;98(3):037204. doi: 10.1103/PhysRevLett.98.037204.
The velocity of domain walls driven by current in zero magnetic field is measured in permalloy nanowires using real-time resistance measurements. The domain wall velocity increases with increasing current density, reaching a maximum velocity of approximately 110 m/s when the current density in the nanowire reaches approximately 1.5 x 10(8) A/cm(2). Such high current driven domain wall velocities exceed the estimated rate at which spin angular momentum is transferred to the domain wall from the flow of spin polarized conduction electrons, suggesting that other driving mechanisms, such as linear momentum transfer, need to be taken into account.
利用实时电阻测量法，在坡莫合金纳米线中测量了零磁场下电流驱动的磁畴壁速度。磁畴壁速度随电流密度的增加而增大，当纳米线中的电流密度达到约1.5×10⁸ A/cm²时，磁畴壁速度达到约110 m/s的最大值。如此高的电流驱动磁畴壁速度超过了自旋极化传导电子流将自旋角动量转移到磁畴壁的估计速率，这表明需要考虑其他驱动机制，如线性动量转移。
