High birefringent anti-resonant hollow-core fiber filled with epsilon-near-zero material

Abstract In the fields of optical communication and optical sensing, hollow-core anti-resonant fibers (HC-ARFs) have attracted significant attention owing to their unique advantages, which are crucial for high birefringence characteristics for expanding their applications. By filling the Epsilon-Near-Zero (ENZ) material in some specific air holes, an HC-ARF with a double anti-resonant layer structure is designed, and the high birefringence is achieved through the synergistic regulation mechanism of materials and structures. Based on the full-vector finite element method, it conducts an in-depth analysis of the influence of structural parameters on the birefringence of the fiber. The results show that for the optimized fiber, the birefringence can reach to 3.7 × 10 –4 at 1.55 μm. This method not only effectively improves the birefringence level of HC-ARFs, but also provides theoretical support for the structural design of high-birefringence hollow-core anti-resonant fibers. It is expected to promote the application of HC-ARFs in the fields of high-speed optical communication, high-sensitivity optical sensing and so on.