Ultra‐Wide Mid‐Infrared Supercontinuum Generation in As ₂ S ₃ Hexagonal‐Core Photonic Crystal Fiber

This work introduces a newly designed As 2 S 3 ‐based photonic crystal fiber structure optimized for generating broadband mid‐infrared supercontinuum under low peak power excitation. The hexagonal‐core configuration enhances both dispersion and nonlinear characteristics by adjusting structural parameters. Two optimized models, F1 ( Λ = 1.0 µm, f = 0.35) and F2 ( Λ = 2.0 µm, f = 0.3), are investigated under femtosecond pulse pumping. Fiber F1 supports all‐normal dispersion and generates a broadband spectrum from 1.8 to 6.5 µm at 3 kW using a 210 fs pulse. In contrast, fiber F2 yields an anomalous regime SC spectrum spanning 1.5‐18 µm under 10 kW peak power and an 85 fs pulse. These findings confirm the applicability of the proposed fibers for MIR applications, such as molecular sensing, spectroscopic analysis, and food quality monitoring.