Mid-infrared Raman soliton generation of orbital angular momentum modes based on fluorotellurate photonic crystal fiber

In this study, the design of a fluorotellurite (TeO 2 –BaF 2 –Y 2 O 3 , TBY) glass hexagonal photonic crystal fiber (PCF) capable of supporting four vector beams—HE 11 , TM 01 , TE 01 , and HE 21 —in the mid-infrared (MIR) waveband is presented. A comprehensive analysis of the characteristics of these vector beams, including their effective refractive index, field distributions, confinement loss, dispersion, and nonlinear coefficient is performed. Furthermore, widely tunable MIR Raman solitons in the OAM 1,1 mode of fluorotellurite fibers, pumped by a 2 µ m OAM 1,1 mode laser with 300 fs pulses, are demonstrated through numerical simulations. Our results indicate that the TBY-PCF we investigated shows great potential for generating MIR orbital angular momentum light sources based on the soliton self-frequency shift effect.