Abstract In this paper, we modeled and fabricated a single-mode microstructured fibre (MOF) based on the solid solution crystals of AgBr–TlI and AgBr–TlBr0.46I0.54 systems. For this purpose, we gained the refractive index dispersion of the given systems in the wavelength range of 19–25 μm. It served as a basis for fibre simulations. The obtained MOF model was 700 μm in diameter; it included 200-μm central insert and 40 quasi-square peripheral inserts with the cross-section of 20 × 20 μm and the pitch of 80 μm and operated in a single-mode regime within the wavelength range of 22–25 μm, while the transmitting range was 2.5–25 μm. It possessed an enlarged mode field when compared to a corresponding single-mode step-index fibre (SIF). This MOF was fabricated using a method, which combines hot pressing and extruding. It was shown that the fundamental mode is tightly confined in the fibre core region. The developed MOF structure may be suitable for producing outputs, splitters, and couplers for various types of solid-state lasers based on semiconductors and gas steam lasers, including ones deployed in a harsh environment.

中文翻译：

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具有放大模场的单模方栅 MOF，用于中红外

摘要 在本文中，我们基于 AgBr-TlI 和 AgBr-TlBr0.46I0.54 系统的固溶体晶体建模并制造了单模微结构光纤 (MOF)。为此，我们获得了给定系统在 19-25 μm 波长范围内的折射率色散。它作为纤维模拟的基础。得到的MOF模型直径为700μm；它包括 200 μm 中心插入件和 40 个准方形外围插入件，横截面为 20 × 20 μm，节距为 80 μm，并在 22-25 μm 波长范围内以单模方式运行，而传输范围为 2.5–25 μm。与相应的单模阶跃折射率光纤 (SIF) 相比，它拥有更大的模场。这种 MOF 是使用热压和挤压相结合的方法制造的。结果表明，基模被严格限制在纤芯区域。开发的 MOF 结构可能适用于生产各种基于半导体和气体蒸汽激光器的固态激光器的输出、分路器和耦合器，包括部署在恶劣环境中的激光器。