Fig. 1. Schematic of the proposed fiber: (a) cross-sectional view and refractive index distribution and (b) side view.

Fig. 2. Contour of coupling coefficient κ with respect to d and D.

Fig. 3. Transmittance spectrum evolution along CPZ fiber.

Fig. 4. Side view of the fabricated CPZ fiber.

Fig. 5. Experimental setup of the Jones matrix method.

Fig. 6. Output polarization ellipses when three linearly polarized lights with different orientations are injected into the CPZ fiber.

Fig. 7. Polarization ellipse of the two eigenstates: (a) left-handed and (b) right-handed.

Fig. 8. Extinction ratios of the two circularly polarized lights.