In this paper, we propose a single-mode laser operating in the mid-infrared regime by exploiting parity-time (PT) breaking in a whispering gallery mode (WGM) micro-resonator based on air-clad hollow-core ZBLAN fibers. By introducing alternate gain–loss modulation regions with refractive indices respectively having the same real parts but opposite imaginary parts into the air hole clad region of the hollow-core fiber infiltrated with optical functional materials, a PT symmetry system could be set up and specific WGM in PT-broken state whose electric field distribution matches the gain–loss modulation pattern can be excited to realize single-mode laser emission around 5 μm. And moreover, simulation results indicate that high precision laser wavelength tuning with a sensitivity of 1.623 nm RIU⁻¹ can be achieved by adjusting the refractive index of the functional materials filled into the cladding air holes.

在本文中，我们通过利用基于空气包层空芯 ZBLAN 光纤的回音壁模式 (WGM) 微谐振器中的奇偶校验时间 (PT) 断裂，提出了一种在中红外区域工作的单模激光器。通过将折射率分别具有相同实部但相反虚部的交替增益-损耗调制区域引入到渗透有光学功能材料的空芯光纤的气孔包层区域，可以建立PT对称系统和特定的WGM在电场分布与增益-损耗调制模式相匹配的 PT 断路状态下，可以被激发以实现 5 μ m左右的单模激光发射。此外，仿真结果表明，具有 1.623 nm RIU ^-1灵敏度的高精度激光波长调谐 可以通过调节填充到包层气孔中的功能材料的折射率来实现。