Recently, within the emerging framework of “lab-on-fiber” technologies, we successfully demonstrated the integration of phase-gradient plasmonic metasurfaces on the tip of an optical fiber. The resulting optical-fiber “meta-tips” promise to empower the typical fiber-optics application scenarios (e.g. sensing, telecommunications, imaging, etc.) with the advanced light-manipulation capabilities endowed by metasurfaces. Here, we explore more in detail the possibility to exploit this platform in label-free biological or chemical sensing applications. Specifically, we carry out a parametric study of the surface sensitivity and show that phase-gradient metasurfaces generally outperform their gradient-free counterparts, without imposing additional fabrication complexity. Therefore, the phase gradient can be effectively exploited as an additional degree of freedom in the design of high-sensitivity devices.

中文翻译：

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用于传感应用的光纤相位梯度元尖端的评估

最近，在新兴的“光纤实验室”技术框架内，我们成功地展示了相位梯度等离子体超表面在光纤尖端的集成。由此产生的光纤“元尖端”有望使典型的光纤应用场景（例如传感、电信、成像等）具有超表面赋予的先进光操纵能力。在这里，我们更详细地探讨了在无标记生物或化学传感应用中利用该平台的可能性。具体而言，我们对表面敏感性进行了参数研究，并表明相位梯度超表面通常优于无梯度超表面，而不会增加额外的制造复杂性。所以，