近日，西班牙马德里先进材料研究所的Francisco Guinea&Pierre A. Pantaleón及其研究团队取得一项新进展。经过不懈努力，他们揭示了扭曲石墨烯多层中超导性的演化过程。相关研究成果已于2024年7月30日在国际知名学术期刊《美国科学院院刊》上发表。

该研究团队深入分析了长程电荷波动对扭曲双双层石墨烯和螺旋三层石墨烯超导性的贡献，并将所得结果与扭曲双层石墨烯进行了系统比较。为此，研究人员采用了依赖于几个公认参数的图解方法。研究发现，双双层石墨烯和螺旋三层石墨烯与扭曲双层石墨烯在临界温度和序参数上存在显著差异。这一趋势与实验结果相吻合，可以与不同系统中莫尔Umklapp过程所起的作用相关联。

据悉，莫尔石墨烯超导体家族不断壮大，迄今为止，已涵盖了扭曲的石墨烯多层结构以及未扭曲的堆叠结构。

附：英文原文

Title: Evolution of superconductivity in twisted graphene multilayers

Author: Long, Min, Jimeno-Pozo, Alejandro, Sainz-Cruz, Héctor, Pantaleón, Pierre A., Guinea, Francisco

Issue&Volume: 2024-7-30

Abstract: The group of moiré graphene superconductors keeps growing, and by now it contains twisted graphene multilayers as well as untwisted stacks. We analyze here the contribution of long-range charge fluctuations in the superconductivity of twisted double bilayers and helical trilayers, and compare the results to twisted bilayer graphene. A diagrammatic approach which depends on a few, well-known parameters is used. We find that the critical temperature and the order parameter differ significantly between twisted double bilayers and helical trilayers on one hand, and twisted bilayer graphene on the other. This trend, consistent with experiments, can be associated with the role played by moiré Umklapp processes in the different systems.

DOI: 10.1073/pnas.2405259121

Source: https://www.pnas.org/doi/abs/10.1073/pnas.2405259121