Fluctuation Characteristics Of Optical Waves Propagated In An Externally Perturbed Birefringent Fiber

A fiber-optic correlation processing system is constructed to examine the fluctuation characteristics of optical waves guided in an externally perturbed birefringent fiber. Optical heterodyne detection processes by use of a laser beam with orthogonal linearly polarized two-frequency components are capable of producing the correlation output of the fluctuating guided HE11 modes. A high-speed phase demodulator is designed to produce the fluctuating phase whose correlation can be computed. By use of these techniques and devices, the dynamic fluctuation-characteristics of the guided modes can be examined for any fluctuation statistics. In the demonstrative experiment each guided wave is stable in intensity and its state of polarization is well preserved for axial vibration but not stable for lateral vibration.