Design of broadband single-polarization single-mode holey fiber

We propose a novel structure of single-polarization single-mode(SPSM) holey fiber designed based on resonant coupling effect. The proposed fiber is able to achieve SPSM operation over an ultra-broad bandwidth as large as 920nm ranging from 1.48µm to 2.4µm, within which only one polarization state of the fundamental mode can be effectively guided. With the aid of six smaller holes around the central core, the effective mode area of the fiber is enlarged and the chromatic dispersion curve is flattened. The numerical results indicate that the proposed fiber achieves nearly zero ultra-flattened dispersion over a wide spectral range and the effective mode area is approaching ∼78µm² at 1550nm. Moreover, the structure shows superiority in output beam quality owing to the symmetry of the central core region, and also exhibits great modal compatibility with SMF.