Multimode hollow-core anti-resonant fiber based on tellurite glass for mid-infrared applications

Abstract Multimode hollow-core anti-resonant (MM-HC-ARF) fiber based on tellurite glass for mid-infrared (mid-IR) applications, which supports eight core modes, namely LP 01 , LP 11 , LP 21 , LP 02 , LP 31 , LP 12 , LP 41 and LP 22 . The designed fiber uses tellurite glass as the base material and a novel structure with double-nested tubes to divide the cladding region, which can effectively suppress mode couplings between the core and the cladding modes. The structural parameters of the MM-HC-ARF are optimized using the finite element method, and the confinement loss (CL) and bending loss (BL) of every core mode are analyzed. The simulation results demonstrate that within the 2.5–3.5 µ m wavelength range, the CL of all modes reaches its minimum at 3 µ m. Among them, the fundamental LP 01 mode exhibits the lowest CL of 7.6 × 10 −6 dB m −1 , while the differential group delay remains above 0.1 ps m −1 throughout this spectral range. Furthermore, when the bending radius exceeds 11 cm, the BL of all modes remains below 0.02 dB m −1 . The proposed double-nested-tube MM-HC-ARF structure exhibits significant potential for applications in optical communication systems.