根据级联半导体光放大器(SOA)的偏振主态对准(PSP)与邦加球相关性之间的关系，研究了多级SOA 级联式系统的偏振主态对准方法。提出了基于非线性偏振旋转效应(NPR)的多级SOA 级联式全光开关结构。实际搭建出两级SOA 级联式全光开关实验系统，并以幅值为6 mW 的方波控制光对50 μW 信号光实现了全光开关操作，开关速度达到200 ps，优于传统的电光开关，并存在较大的提升空间。工作波段位于1510~1570 nm，插损为3.62 dB，功耗为12 mW。开关速度快、插损小、功耗低并与光纤通信系统兼容性好。该全光开关的研制成功，将有助于推动全光开关和全光网络技术的发展，以及光计算和全光信号处理等领域的技术进步。

The principle states of polarization (PSP) alignment in multilevel cascaded semiconductor optical amplifiers (SOA) system are studied based on the relationship between their PSP alignment and Poincare Sphere′ s correlation. Scheme of the all- optical switch is proposed based on nonlinear polarization rotation (NPR) in multilevel cascaded SOAs. An all- optical switch is demonstrated based on NPR in two cascaded SOAs. A light signal of 50 μW is all- optically switched by a square wave control light of 6 mW, and the switching speed is 200 ps. The all- optical switch′ s wavelength band is from 1510 nm to 1570 nm, and its insertion loss is 3.62 dB and power consumption is 12 mW. The all- optical switch has advantages like high switching speed, low insertion loss and power consumption, and good compatibility with optical fiber communication system and will effectively promote the technology development in all-optical switch field and all-optical network field, as well as optical computing field and all-optical signal processing field.