Detailed polarization properties comparison for three completely different species of highly birefringent fibers

We present a detailed experimental investigation for four dgerent fiber samples: a standard PANDA pber, two index-guiding nonlinear photonic crystal fibers. and an air-core photonic bandgap $her. Although all fibers exhibit large birefringence, their polarization properties are found to be quite different. Most surprisingly, the principle states of polarization strongly vary with wavelength for the photonic bandgap pber, indicating the presence of polarization mode coupling.