Geometric-phase polarimetry

This paper describes polarimetric strategies based on measuring the light's geometric phase, which results from the evolution of the polarisation state while traversing an optical system. The system in question is described by a homogeneous Jones matrix, which by definition, contains mutually perpendicular eigenpolarisations. Our leading theory links the system's Jones matrix parameters (eigenvalues and eigenvectors) with the input polarisation state and the geometric phase. We demonstrate two interferometric techniques. The first one measures the geometric phase based on the relative lateral fringe displacement between the interference pattern of two mutually-orthogonal polarisation states. The second technique uses the visibility of the interference fringes to determine the eigenpolarisations of the system. We present proof-of-principle experiments for both techniques.