Large Mode Area Single Mode Fiber with a Twisted Polygon-Shaped Core

We present numerical studies on twisted polygon-shaped core fibers for achieving single mode operation with a large area propagation in this paper. These can achieve due to twisting-induced high losses higher order modes and coupling leaky modes. A tail-like profile will appear when they couple modes, the also indicates that these carry angular momentum. Numerical simulations show octagon-shaped fiber diameter of 80 μm obtain first larger than 19 dB/m while maintaining fundamental at about 0.15 dB/m. In case heptagon-shaped core, an design exists more 17 less 0.14 losses.