Twisting a route for surface plasmons Graphene is an atomically thin material that supports highly confined plasmon polaritons, or nano-light, with very low loss. The properties of graphene can be made richer by introducing and then rotating a second layer so that there is a slight angle between the atomic registry. Sunku et al. show that the moiré patterns that result from such twisted bilayer graphene also provide confined conducting channels that can be used for the directed propagation of surface plasmons. Controlling the structure thereby provides a pathway to control and route surface plasmons for a nanophotonic platform. Science, this issue p. 1153 Twisted bilayer graphene hosts periodic arrays of conducting channels for the directed propagation of surface plasmons. Graphene is an atomically thin plasmonic medium that supports highly confined plasmon polaritons, or nano-light, with very low loss. Electronic properties of graphene can be drastically altered when it is laid upon another graphene layer, resulting in a moiré superlattice. The relative twist angle between the two layers is a key tuning parameter of the interlayer coupling in thus-obtained twisted bilayer graphene (TBG). We studied the propagation of plasmon polaritons in TBG by infrared nano-imaging. We discovered that the atomic reconstruction occurring at small twist angles transforms the TBG into a natural plasmon photonic crystal for propagating nano-light. This discovery points to a pathway for controlling nano-light by exploiting quantum properties of graphene and other atomically layered van der Waals materials, eliminating the need for arduous top-down nanofabrication.

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莫尔石墨烯超晶格中用于纳米光的光子晶体

扭转表面等离子体激元的路线 石墨烯是一种原子级薄的材料，支持高度受限的等离子体激元或纳米光，损耗非常低。石墨烯的特性可以通过引入然后旋转第二层来变得更丰富，这样原子注册之间就有一个微小的角度。Sunku 等人 表明由这种扭曲的双层石墨烯产生的莫尔图案也提供了可用于表面等离子体的定向传播的受限导电通道。从而控制结构为纳米光子平台提供了控制和路由表面等离子体的途径。科学，这个问题 p。1153 扭曲双层石墨烯承载着用于表面等离子体的定向传播的导电通道的周期性阵列。石墨烯是一种原子级薄的等离子体介质，以极低的损耗支持高度受限的等离子体激元或纳米光。当石墨烯铺在另一个石墨烯层上时，它的电子特性会发生巨大变化，从而产生莫尔超晶格。两层之间的相对扭曲角是由此获得的扭曲双层石墨烯（TBG）层间耦合的关键调谐参数。我们通过红外纳米成像研究了 TBG 中等离子体激元的传播。我们发现以小扭转角发生的原子重建将 TBG 转化为用于传播纳米光的天然等离子体光子晶体。这一发现指出了通过利用石墨烯和其他原子层状范德华材料的量子特性来控制纳米光的途径，