Fig. 1. (a) Schematic cross-section of the proposed fiber structure. (b) Refractive index profile of the proposed optical fiber.

Fig. 2. (a) Surface profile of the power flow of the FM and the first HOM of the two fibers at 1.06 μm. (b) Modal refractive indices of the FM (green), first HOM (red), and ARE FM (blue) as a function of d/D. (c) Modal refractive indices of the FM (solid), first HOM (dashed), and ARE FM (dashed and dotted) of Fiber 1 (red) and Fiber 2 (black) at 1 μm.

Fig. 3. (a) The FM (solid) and first HOM (dashed) leakage loss for Fiber 1 (red) and Fiber 2 (black). (b) HOM suppression for the fibers in (a).

Fig. 4. (a) The FM (solid) and first HOM (dashed) leakage loss under D = 40 μm (red), 60 μm (green), 80 μm (blue), and 100 μm (navy). (b) HOM suppression for the fibers in (a). (c) The FM (square) and first HOM (triangle) leakage loss with increased core diameter. (d) HOM suppression under different core sizes.

Fig. 5. The legend of some structures described in Table 2 .

Fig. 6. (a) The FM (squares) and first HOM (triangles) leakage loss for three index depression values with increasing core diameter. (b) HOM suppression for different Δn.