Polarization singularities and fiber modal decomposition

Abstract

Interference of fiber eigen vector modes of different phase and spatial variation of polarization gives rise to different types of polarization singularities-isolated C-point surrounded by star/lemon type polarization morphology patterns, a dipole or two C-points of same index-in 2D polarization fields. In this context, fiber modal decomposition refers to identifying the constituent modes, their relative amplitude and the phase relationship among them in the fiber output. The size and location of the L-contour and the location of Cpoints determine the relative amplitude and the orientation of the polarization morphology pattern provides information regarding the relative phase difference between the constituent vector modes. We use these aspects of polarization singularity to demonstrate a novel fiber modal decomposition method. © 2013 SPIE.