Nanosecond spin relaxation times in single layer graphene spin valves with hexagonal boron nitride tunnel barriers
Nanosecond spin relaxation times in single layer graphene spin valves with hexagonal boron nitride tunnel barriers
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DOI：
10.1063/1.4962635
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发表时间：
2016-09-19
影响因子：
4
通讯作者：
Kawakami, Roland
中科院分区：
文献类型：
--
作者：
Singh, Simranjeet;Katoch, Jyoti;Kawakami, Roland
我们用六方氮化硼(h-BN)原子片作为自旋注入的隧道势垒，对单层石墨烯中的自旋输运进行了实验研究。虽然h-BN有望有利于自旋注入，但之前的实验研究一直无法在纳秒范围内实现自旋弛豫时间，这表明潜在的问题源于接触。在这里，我们研究了具有h-BN势垒的石墨烯自旋阀的自旋弛豫，并观察到室温自旋寿命超过一纳秒，这为实验证实h-BN确实是一种良好的自旋注入石墨烯的势垒材料。通过对不同厚度的h-BN的测量表明，在石墨烯中，较少的h-BN层比单层膜更有利于获得高的非局域自旋信号和更长的自旋弛豫时间。由AIP出版公司出版。
We present an experimental study of spin transport in single layer graphene using atomic sheets of hexagonal boron nitride ( h-BN) as a tunnel barrier for spin injection. While h-BN is expected to be favorable for spin injection, previous experimental studies have been unable to achieve spin relaxation times in the nanosecond regime, suggesting potential problems originating from the contacts. Here, we investigate spin relaxation in graphene spin valves with h-BN barriers and observe room temperature spin lifetimes in excess of a nanosecond, which provides experimental confirmation that h-BN is indeed a good barrier material for spin injection into graphene. By carrying out measurements with different thicknesses of h-BN, we show that few layer h-BN is a better choice than monolayer for achieving high non-local spin signals and longer spin relaxation times in graphene. Published by AIP Publishing.