OPTICAL-FIBER POLARIZER BASED ON HIGHLY BIREFRINGENT SINGLE-MODE FIBER

An in-line fiber polarizer is proposed and demonstrated. The attenuati on of a single-mode fiber experiencing an axial periodic perturbation shows peaks at certain wavelengths, resulting from the power coupling between the guided mode and the cladding modes. When the fiber has sig nificant linear birefringence, each of these peaks is split into two p eaks. The fiber thus exhibits polarization-selective attenuation chara cteristics. An example of such a polarizer is demonstrated based on a highly birefringent fiber with a beat length of 1.3 mm. A 25-dB polari zation extinction ratio is obtained, with an attenuation of 1.3 dB at an operating wavelength of 1177 nm.