All‐Dielectric Fiber Meta‐Tip Enabling Vortex Generation and Beam Collimation for Optical Interconnect

Abstract “Lab‐on‐fiber” technology, which combines the unique merits of optical fibers with nanophotonic platforms, has received significant investigation due to its profound ability to control light at the nanoscale, which has significantly boosted the functionalities of conventional fibers. Previous plasmonic‐based fiber meta‐tips (FMTs) have been inhibited by the intrinsic ohmic losses of the metallic structures, resulting in limited light manipulation efficiency. In addition, to become prominent candidates for integrated photonics, their functional diversity needs to be enhanced. In this study, an FMT constructed by tethering an all‐dielectric metasurface to a single‐mode fiber for bifunctional light manipulation is implemented. Distinct light manipulation, including vortex generation and beam collimation, is executed by tailoring the phase profiles encoded in the metasurface for transverse electric and transverse magnetic polarized light. To build the proposed FMT, a polarization‐selective metasurface is first created via lithography nanofabrication and then attached to an optical fiber with the aid of a vision system. Moreover, as a proof‐of‐concept, the feasibility of exploiting the established FMT for applications such as optical interconnects is demonstrated. The resulting fiber optics and metasurface‐based meta‐tip represent a major breakthrough in the lab‐on‐fiber technology roadmap for applications such as optical communication, optical trapping, and biological sensing.