一种低弯曲损耗全固态单模光纤

A low bending loss all solid state single-mode fiber

摘要:

针对传统光纤在小弯曲半径下弯曲损耗过高的问题，本文提出了一种具有低弯曲损耗的单模光纤。通过在光纤包层中嵌入高折射率介质管，可以实现包层模与高阶模之间的能量耦合。这种方法能够有效地使高阶模在传输过程中因高损耗而被有效滤除，从而确保了单模传输的特性。同时通过利用纤芯与包层之间的高折射率差，基模能够有效地被限制在纤芯中，从而实现光纤的低弯曲损耗传输。采用全矢量有限元法进行仿真，结果显示：当工作波长为1.55μm，弯曲半径为5mm时，基模的最小弯曲损耗可低至0.001dB/m。此外，该光纤的单模带宽约为0.55μm，在1.55μm波长下的模场直径为9.10μm，拼接损耗最低可达5.03×10-4dB，与标准单模光纤具有良好的兼容性。

Abstract:

To address the excessive bending loss of conventional optical fibers at small bending radii, this study proposes a low-bending-loss single-mode fiber. By embedding high-refractive-index dielectric tubes in the fiber cladding, energy coupling between cladding modes and higher-order modes is achieved. This approach effectively filters out higher-order modes through their elevated transmission losses, thereby preserving single-mode propagation characteristics. Simultaneously, the large refractive index contrast between the core and cladding enables strong confinement of the fundamental mode within the core, achieving low bending loss. The simulation using the full-vector finite element method demonstrate that at an operating wavelength of 1.55μm with a bending radius of 5mm, the minimum bending loss of the fundamental mode reaches 0.001dB/m. Furthermore, the fiber exhibits a single-mode bandwidth of approximately 0.55μm, a mode field diameter of 9.10μm at 1.55μm, and splicing loss as low as 5.03×10??dB, demonstrating excellent compatibility with standard single-mode fibers.