标题： WISPFI 实验：原型开发 显示英文标题

标题： WISPFI Experiment: Prototype Development

摘要： 轴子和类轴子粒子（ALPs）是与光子在外部磁场中耦合的有吸引力的暗物质（DM）候选者。 围绕$m_a \sim 50~\mu$eV 的参数空间尚未被haloscope实验广泛探索。 我们介绍了WISP Searches on a Fiber Interferometer（WISPFI）的第一个原型，这是一种基于共振光子-轴子转换的桌面型、模型无关的方案，该方案利用集成到马赫-曾德尔干涉仪（MZI）中的空心芯光子晶体光纤（HC-PCF）。 在暗条纹附近运行并采用主动相位锁定，结合幅度调制，该干涉仪将轴子引起的光子消失转化为可测量的信号。 一个2 W、1550 nm的激光被耦合进放置在2 T永磁体阵列内的1米长的HC-PCF中，探测固定轴子质量为$m_a \simeq 49~$meV，测量时间为30天时的预期灵敏度为$g_{a\gamma\gamma} \gtrsim 1.3 \times 10^{-9}~\text{GeV}^{-1}$。 未来的升级包括有效折射率的压力调谐和法布里-珀罗腔的实现，可以扩展可访问的质量范围并提高灵敏度，从而将WISPFI确立为一种可扩展的平台，以探索之前无法触及的轴子参数空间区域。 显示英文摘要

摘要： Axions and axion-like particles (ALPs) are well-motivated dark matter (DM) candidates that couple to photons in external magnetic fields. The parameter space around $m_a \sim 50~\mu$eV remains largely unexplored by haloscope experiments. We present the first prototype of WISP Searches on a Fiber Interferometer (WISPFI), a table-top, model-independent scheme based on resonant photon-axion conversion in a hollow-core photonic crystal fiber (HC-PCF) integrated into a Mach-Zehnder interferometer (MZI). Operating near a dark fringe with active phase-locking, combined with amplitude modulation, the interferometer converts axion-induced photon disappearance into a measurable signal. A 2 W, 1550 nm laser is coupled into a 1 m-long HC-PCF placed inside a 2 T permanent magnet array, probing a fixed axion mass of $m_a \simeq 49~$meV with a projected sensitivity of $g_{a\gamma\gamma} \gtrsim 1.3 \times 10^{-9}~\text{GeV}^{-1}$ for a measurement time of 30 days. Future upgrades, including pressure tuning of the effective refractive index and implementation of a Fabry-P\'erot cavity, could extend the accessible mass range and improve sensitivity, establishing WISPFI as a scalable platform to explore previously inaccessible regions of the axion parameter space.