In this paper, a new circular photonic crystal fiber (PCF) is designed, which can support stable transmission of 30 orbital angular momentum (OAM) modes. It is composed of 4 rings of air holes in the cladding and a large air hole in the center. The numerical results show that the fiber has good features. In the wavelength range of 1.35–1.8 μm, dispersion variations are less than 27.99 ps/nm/km when the order of OAM mode is less than 6. The confinement losses of most vector modes are lower than 10⁻⁸ dB/m at the wavelength of 1.55 μm. Nonlinear coefficients are below 4.144 W⁻¹/km in the whole bandwidth. In addition, all modes have higher purity and the highest mode purity can reach 99.78%. Moreover, the influence of elliptical deformation on this fiber is also considered. The results indicate that the fiber has good tolerance to elliptical deformation. All these properties show that the designed PCF will play an important role in optical communication systems in the future.

本文设计了一种新型的圆形光子晶体光纤（PCF），它可以支持30种轨道角动量（OAM）模式的稳定传输。它由包层中的4个气孔环和中心的大气孔环组成。数值结果表明该纤维具有良好的特性。在1.35–1.8μm的波长范围内，当OAM模式的阶次小于6时，色散变化小于27.99 ps / nm / km。大多数矢量模式的限制损耗在^10〜8 dB / m以下。波长为1.55μm。非线性系数低于4.144 W ^-1/ km。此外，所有模式均具有更高的纯度，最高模式纯度可达到99.78％。此外，还考虑了椭圆形变形对该纤维的影响。结果表明该纤维对椭圆形变形具有良好的耐受性。所有这些特性表明，设计的PCF将来将在光通信系统中扮演重要角色。