The isolated cyclo[18]carbon (C₁₈), as a newly synthesized carbon allotrope, has potential to become the core unit of high‐end electronic devices due to its excellent physical properties. However, the research on C₁₈ in molecular devices is still in the rudimentary stage. Herein, a novel molecular spin‐filtering device, formed by covalently sandwiching a C₁₈ ring between two zigzag‐edged graphene nanoribbons (ZGNRs), is investigated based on the nonequilibrium Green's function method and density functional theory. It is found that the spin‐polarized current can be implemented and controlled through adjusting the magnetic configuration of left (right) electrode. Remarkably, a strong bimolecular configuration switching effect can be achieved by inserting a metal carbon chain between nonmagnetic ZGNRs and C₁₈ (on/off ratio of ≈2737). The results suggest theoretical guidance for the design of next‐generation carbon‐based molecular spintronic devices.

中文翻译：

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环[18]碳基分子器件中的巨开关效应和自旋电子输运性质

作为新合成的碳同素异形体，孤立的环[18]碳（C ₁₈）由于其优异的物理性能而有可能成为高端电子设备的核心单元。但是，对分子装置中的C ₁₈的研究仍处于起步阶段。在这里，一种新的分子自旋过滤装置，是通过共价夹心C ₁₈形成的基于非平衡格林函数方法和密度泛函理论，研究了两个曲折边缘的石墨烯纳米带（ZGNR）之间的环。发现可以通过调节左（右）电极的磁性配置来实现和控制自旋极化电流。值得注意的是，可以通过在非磁性ZGNR和C ₁₈之间插入金属碳链来实现强大的双分子构型转换效果（开/关比约为2737）。结果为下一代碳基分子自旋电子器件的设计提供了理论指导。