High-Mode Purity 1 μm Cylindrical Vector Beam All-Fiber Laser Based on a Symmetric Two-Mode Coupler. - Yang, Boyi; Pei, Siqi; Zhang, Tianyu; Zhang, Yizhuo; Hao, He; Zhang, Kun; Liu, Xuesheng; Lan, Tian; Yan, Anru; Liu, Youqiang; Wang, Zhiyong (Applied Sciences (2076-3417), 2023)