Sensitive optical experiments in fiber, including for applications in communications and quantum information, are limited by the noise generated when light scatters from thermally excited guided-acoustic phonons. Novel fibers, such as microstructured fibers, offer control over both optical and acoustic waveguide properties, which can be designed to mitigate optomechanical noise. Here, we investigate the optomechanical properties of microstructured anti-resonant hollow-core fibers and demonstrate their promise as a low-noise fiber platform. By developing an ultra-sensitive spectroscopy technique, a seven capillary anti-resonant hollow-core fiber is found to exhibit record low optomechanical coupling (<10⁻⁴ W⁻¹ m⁻¹), in agreement with comprehensive numerical calculations. The largest scattering occurs from a guided acoustic mode in the air confined in the core of the fiber. Acoustic resonances in the silica, due to minimal overlap with the optical mode in the core, scatter a hundred times less, resulting in negligible depolarization noise. The largest optomechanical interactions in anti-resonant hollow-core fibers are found to be at least three (five if evacuated) orders of magnitude weaker than those in conventional single-mode fibers, which makes this class of fibers a promising platform for low noise applications, including quantum information processing and optical communication.

中文翻译：

---

反共振空心纤维中的超低布里渊散射

光纤中的敏感光学实验（包括用于通信和量子信息中的实验）受到光从热激发的引导声子散射时产生的噪声的限制。新型纤维（例如微结构纤维）可以控制光学和声学波导特性，可以设计为减轻光机械噪声。在这里，我们研究了微结构抗共振空心纤维的光机械性能，并证明了它们作为低噪声纤维平台的前景。通过开发超灵敏光谱技术，发现七根毛细管反共振空心光纤表现出创纪录的低光机耦合（<10 ^-4 W ^-1 m ^-1），并与全面的数值计算相一致。最大的散射来自被限制在光纤纤芯中的空气中的引导声模。由于与纤芯中光学模式的重叠很小，二氧化硅中的声共振散射少了100倍，导致去极化噪声可忽略不计。发现反共振空心光纤中最大的光机械相互作用至少比传统的单模光纤弱三个数量级（如果疏散则为五个），这使得此类光纤成为低噪声应用的有希望的平台，包括量子信息处理和光通信。