Superlative Spin Transport In Few-layer Graphene With Cobalt Intercalation

Electronic transport in single or a few layers of graphene is the subject of intense interest at present. However, the current graphene-based spin transport devices have short spin relaxation lengths and relaxation times, low self-selective injection efficiency, and the research on its mechanism is relatively vague. Here, we study gate-tunable spin transport across few-layer graphene spin valves which enable us to systematically investigate spin transport under non-local geometry. We achieved significent non-local resistence signals reaching 50 Ω and spin lifetimes exceeding 10 ns. We have demonstrated that while retaining the excellent electrical properties of graphene, the intercalation of cobalt atoms in few-layer graphene achieves spin coupling and vastly promotes the improvement of spin injection efficiency.