Polarization-maintaining fiber composed of an elliptical ring core and two circular air holes

In this paper, a new polarization-maintaining fiber (PMF) composed of an elliptical ring core and two circular air holes is exploited. The PMF could support 10 guided modes with refractive index differences 1n_eff of all the adjacent modes larger than 10⁻⁴. Moreover, the optimum parameters of the PMF covering the entire C + L band are obtained. Last, the chromatic dispersion Dof the designed elliptical ring core fiber, the confinement loss α, and the power fraction χ of the two-air core are calculated. The calculation results show that D, α, and χ are compatible with traditional step-index fiber, and the designed elliptical ring core fiber is suitable for mode-division multiplexing and optical fiber sensors.