In plasmonic guided waves, material absorption is generally an unwanted shortcoming that degrades the quality of plasmon modes by greatly curtailing their propagation distance. In this work, we explore the general features of the modal properties supported by 2D anisotropic materials and elucidate how the material’s in-plane anisotropy can offer a previously untenable level of control or tailoring over plasmonic waveguide design. In particular, we find that utilizing the in-plane anisotropy of anisotropic 2D materials in the conductivity of ribbon films, it is possible to significantly manipulate the modal loss of the plasmonic guided modes by increasing the material absorption of the 2D materials. The physical root cause of this behavior is control over the various electric field components within the film by utilizing the material dispersion of the anisotropic film. This control allows for the ability to manipulate at will, for a wide a range of structure parameters and wavelengths, the net field within the ribbon arising from the interplay between the two edge modes, which constitute the film edges. The findings thus unlock beneficial capabilities offered by using natural 2D anisotropic materials such as black phosphorous in the design of active/passive nano-scale circuits. Furthermore, when these effects are employed in gain media composed of 2D materials, the ability for the realization of low modal loss plasmonic modes concomitant with the presence of substantial material absorption can introduce a new design paradigm that promises novel and enhanced functionality.

中文翻译：

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通过调节材料吸收量来调整各向异性二维材料带中的模态损耗

在等离激元导波中，材料吸收通常是一个不希望有的缺点，它会通过大大减小其传播距离而降低等离激元模的质量。在这项工作中，我们探索了2D各向异性材料支持的模态特性的一般特征，并阐明了材料的面内各向异性如何能够提供对等离激元波导设计以前无法控制的水平或进行定制。特别是，我们发现利用各向异性2D材料在带状薄膜导电率中的面内各向异性，可以通过增加2D材料的材料吸收来显着控制等离激元引导模的模态损耗。此行为的物理根本原因是通过利用各向异性薄膜的材料分散来控制薄膜内的各种电场分量。这种控制允许在很宽的结构参数和波长范围内随意操纵色带内的净场的能力，该净场是由构成胶片边缘的两个边缘模式之间的相互作用引起的。因此，这些发现释放了在有源/无源纳米级电路设计中使用天然2D各向异性材料（例如黑磷）所提供的有益功能。此外，当这些效果用于由2D材料组成的增益媒体时，