Single-polarization Hybrid Hollow-core Anti-resonant Fiber Designs at 2 $μ$m

Abstract

In this letter, to the best of our knowledge, a new type of hollow-core anti-resonant fiber (HC-ARF) design using hybrid silica/chalcogenide cladding is presented for singlepolarization, high-birefringence, and endlessly single-mode operation at 2 m wavelength. We show that the inclusion of a chalcogenide layer in the cladding allows strong suppression of -polarization, while maintaining low propagation loss and singlemode propagation for -polarization. The optimized HC-ARF design includes a combination of low propagation loss, highbirefringence, and polarization-extinction ratio (PER) or loss ratio of 0.02 dB/m, 1.2×10 −4 , >550 respectively, while the loss of the -polarization is >20 dB/m. The proposed fiber may also be coiled to small bend radii while maintaining low bend-loss of ≈ 0.01-0.1 dB/m, and can potentially be used as polarization filter based on the different gap separations and bend conditions.