Single-mode high-power delivery of a 9.3 μm CO ₂ laser by a chalcogenide anti-resonant hollow-core fiber

Chalcogenide-based anti-resonant hollow-core fibers (AR-HCFs) demonstrate significant potential for high-power, high-beam-quality long-wave infrared applications, such as CO₂ laser surgery and precision material processing. Utilizing Ge₁₂As₂₄S₆₄ glass with its favorable viscosity-temperature characteristics, we fabricated a six-capillary non-touching AR-HCF that exhibited exceptional structural uniformity over 15-meter lengths. The optimized fiber achieved a record-low loss of 1.2 dB/m at 9.3 μm and demonstrated unprecedented power handling capabilities by transmitting 8.6 W of input power and delivering 3.5 W of output, which is the highest performance reported for a chalcogenide AR-HCF at this wavelength. Furthermore, the fiber exhibited a beam-cleaning effect, yielding an output beam with superior quality to the input. These advances establish chalcogenide AR-HCFs as promising candidates for demanding long-wave infrared applications that require both high power delivery and excellent beam quality.