As spintronic devices become more and more prevalent, the desire to find Pt-free materials with large spin Hall effects is increasing. Previously it was shown that β-W, the metastable A15 structured variant of pure W, has charge-spin conversion efficiencies on par with Pt, and it was predicted that β-W/Ta alloys should be even more efficient. Here we demonstrate the enhancement of the spin Hall ratio (SHR) in A15-phase β-W films doped with Ta (W 4− x Ta x where x = 0.34 ± 0.06) deposited at room temperature using DC magnetron co-sputtering. In close agreement with theoretical predictions, we find that the SHR of the doped films was ∼9% larger than pure β-W films. We also found that the SHR’s in devices with Co 2 Fe 6 B 2 were nearly twice as large as the SHR’s in devices with Co 4 Fe 4 B 2 . This work shows that by optimizing deposition parameters and substrates, the fabrication of t...

中文翻译：

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掺杂引起的A15相，掺Ta的β-W薄膜的自旋霍尔比提高

随着自旋电子器件变得越来越普遍，寻找具有大自旋霍尔效应的无Pt材料的需求在增加。先前已证明，β-W是纯W的亚稳A15结构变体，具有与Pt相当的电荷自旋转换效率，并且据预测，β-W/ Ta合金应该更有效。在这里，我们证明了在室温下使用直流磁控管共溅射沉积的掺有Ta（W 4-x Ta x，x = 0.34±0.06）的A15相β-W薄膜中自旋霍尔比（SHR）的增强。与理论预测非常吻合，我们发现掺杂薄膜的SHR比纯β-W薄膜大约9％。我们还发现，带有Co 2 Fe 6 B 2的器件中的SHR几乎是带有Co 4 Fe 4 B 2的器件中的SHR的两倍。