超穎透鏡結合單模光纖應用在1550nm光通訊波長

Abstract

超穎透鏡是二維結構，可以完全控制光的振幅、相位和偏振。矽結構具有高傳輸率、低損耗以及與現有半導體技術的兼容性。最近，在「lab-on-fiber」技術的新興框架內，奈米尺度上控制光的強大能力而受到了廣泛的研究。由此產生的光纖「meta-tips」有望為典型的光纖應用場景（例如感測、電信、成像等）提供超表面賦予的先進光操縱功能。在這裡，將使用半導體製程技術來完成超穎透鏡製做。首先，先在玻璃柱基板上選擇矽當作元件材料，之後利用電子束微影的技術(正光阻)產生出奈米結構線寬的圖形，最後再透過lift off 以及由上至下的蝕刻得到矽奈米柱。將做好的超穎透鏡與光纖做結合，成功量測到在1550nm波段的入射光，通過自製超穎透鏡有著聚焦點的效果。聚焦效果為60%。

The meta-lens is a two-dimensional structure that can fully control the amplitude, phase, and polarization of light. The silicon structures offer high transmission rates, low losses, and compatibility with existing semiconductor technologies. Recently, within the emerging framework of "lab-on-fiber" technology, the powerful ability to control light at the nanoscale has been widely researched. The resulting fiber-optic "meta-tips" are expected to provide advanced light manipulation capabilities for typical fiber optic applications such as sensing, telecommunications, imaging, etc., endowed by the meta-lens. Here, semiconductor fabrication techniques will be employed to create the meta-lens. Initially, silicon is chosen as the component material on a glass rod substrate. Subsequently, patterns with nanoscale structure linewidths are generated using electron-beam lithography with positive photoresist. Finally, silicon nanocolumns are obtained through lift-off and top-down etching. The completed meta-lens is then integrated with the optical fiber. Successful measurements of incident light at 1550nm wavelength have been achieved, demonstrating a focusing effect with a 60% efficiency.