We describe the history, guiding mechanism, recent advances, applications, and future prospects for hollow-core negative curvature fibers. We first review one-dimensional slab waveguides, two-dimensional annular core fibers, and negative curvature tube lattice fibers to illustrate the inhibited coupling guiding mechanism. Antiresonance in the glass at the core boundary and a wavenumber mismatch between the core and cladding modes inhibit coupling between the modes and have led to remarkably low loss in negative curvature fibers. We also summarize recent advances in negative curvature fibers that improve the performance of the fibers, including negative curvature that increases confinement, gaps between tubes that increase confinement and bandwidth, additional tubes that decrease mode coupling, tube structures that suppress higher-order modes, nested tubes that increase guidance, and tube parameters that decrease bend loss. Recent applications of negative curvature fibers are also presented, including mid-infrared fiber lasers, micromachining, and surgical procedures. At the end, we discuss the future prospects for negative curvature fibers.

中文翻译：

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负曲率纤维

我们描述了空心负曲率纤维的历史，指导机制，最新进展，应用和未来前景。我们首先回顾一维平板状波导，二维环形芯纤维和负曲率管晶格纤维，以说明受抑制的耦合引导机制。玻璃在纤芯边界处的反共振以及纤芯和包层模之间的波数失配会抑制模之间的耦合，并导致负曲率光纤中的损耗明显降低。我们还总结了负曲率光纤在改善光纤性能方面的最新进展，包括提高约束的负曲率，增加约束和带宽的管之间的间隙，减少模耦合的其他管，抑制高阶模的管结构，嵌套的管可以增加导向，而管参数则可以减少弯曲损耗。还介绍了负曲率光纤的最新应用，包括中红外光纤激光器，微机械加工和外科手术程序。最后，我们讨论了负曲率纤维的未来前景。