The techniques of propagating spin-wave spectroscopy and current-induced spin-wave Doppler shift are applied to a 20-nm-thick Fe/MgO(001) film. The magnetic parameters extracted from the position of the spin-wave resonance peaks are very close to those tabulated for bulk iron. From the zero-current propagating wave forms, a group velocity of 4 km/s and an attenuation length of about 6 $\mu \mathrm{m}$ are extracted for 1.6-$\mu \mathrm{m}$-wavelength spin wave at 18 GHz. From the measured current-induced spin-wave Doppler shift, we extract a surprisingly high degree of spin polarization of the current of $83\%$, which constitutes the main finding of this work. This set of results makes single-crystalline iron a promising candidate for building devices utilizing high-frequency spin waves and spin-polarized currents.

中文翻译：

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单晶铁膜中的自旋波传播和自旋极化电子传输

传播自旋波谱技术和电流感应自旋波多普勒频移技术已应用于20 nm厚的Fe / MgO（001）薄膜。从自旋波共振峰的位置提取的磁参数非常接近于批量铁的列表中列出的参数。从零电流传播波形看，群速度为4 km / s，衰减长度约为6$\mu \mathrm{米}$ 提取为1.6-$\mu \mathrm{米}$-18 GHz的波长自旋波。从测得的电流感应自旋波多普勒频移中，我们提取出了令人惊讶的电流自旋极化高度$83％$，这是这项工作的主要发现。这组结果使单晶铁成为利用高频自旋波和自旋极化电流的建筑设备的有前途的候选者。