M. Mujat, A. Dogariu, and G. S. Agarwal, Interferometric measurement of the degree of polarization and control of the contract of intensity fluctuations, Opt. Lett. (in press)
Abstract: We introduce a technique for determining polarimetric characteristics of light by measuring the contrast of the intensity fluctuations in an interferometric setup. The method permits simultaneous measurement of the degree of polarization and of the second normalized Stokes component, which is related to the ellipsometric parameters azimuth and ellipticity, based on only two measurements. We also show that using phase modulation the signal-to-noise ratio can be increased up to 40% in certain conditions.
J. Ellis and A. Dogariu, Differentiation of globally depolarized complex random fields, JOSA A (in press)
Abstract: Different types of random vector fields can be depolarized in a global sense. They can be physically discriminated by probing the statistical invariance when subject to operations such as a change of the reference frame or the introduction of an arbitrary retardance. Using the Observable Polarization Sphere sphere as a visualization tool, a set of measurements is capable of discriminating between certain types of globally depolarized light and we discuss the geometric interpretation of the physical invariances.
J. Ellis and A. Dogariu, "Complex degree of mutual polarization", Opt. Lett. 29(6), 536-538 (2004)
Abstract: Starting from the concepts of coherence and polarization, we generalize the conventional degree of polarization, introducing a two-point parameter, the complex degree of mutual polarization V, which is defined in terms of measurable quantities. We demonstrate the physical significance of this new quantity for the case of fully correlated, pure states of polarization at the two points, showing that the magnitude of V is a measure of the similarity between the states of polarization at two different points in space.
I. Berezhnyy and A. Dogariu, "Polarimetric description of superposing random electromagnetic fields with different spectral composition", JOSA. A 21(2), 218-222 (2004)
Abstract: We present a polarimetric technique that provides a complete description of a mixture of uncorrelated optical fields with different spectral and polarization properties. The second-order coherence theory is used to describe the superposition of two random optical fields, and an imaging experiment is reported that illustrates the capability to separate radiations with different spectral composition and to simultaneously determine their Stokes vectors.
M. Mujat and A. Dogariu, "Polarimetric and Spectral Changes in Random Electromagnetic Fields", Opt. Lett. 28(22), 2153-2155 (2003)
Abstract: Beginning with a recently formulated unified theory of coherence and polarization for random electromagnetic fields, we show how partially polarized light can be generated through correlation of unpolarized components. The effect is demonstrated by use of a Mach-Zehnder interferometer, showing the possibility of producing light with adjustable spectral density and an adjustable degree of polarization.
J. Ellis, P. Caillard and A. Dogariu, "Off-Diagonal Mueller Matrix Elements in Backscattering from Highly Diffusive Media", JOSA A 19(1), 43-48 (2002)
Abstract: Measurements of a reduced Mueller matrix in backscattering from highly diffusive, dielectric samples are reported as a function of the angle of incidence. It was found that the off-diagonal terms depend greatly on the angle of incidence, increasing to a maximum near grazing incidence. We show that, despite a significant scattering originating in the bulk of such diffusive media, the nontrivial behavior of the off-diagonal Muller matrix is primarily due to surface scattering phenomena. The experimental data can be simply explained by assuming a random orientation of small particles and considering only double scattering in the plane of the surface.
M. Mujat and A. Dogariu, "Real-time measurement of the polarization transfer function" Appl. Opt. 40(1), 34-44 (2001)
Abstract: We present a simple method for measuring the Mueller matrix associated with a scattering medium. Without involving moving parts, four input states of polarization are generated sequentially, and for each of them all four Stokes vector parameters are simultaneously measured for the complete determination of the Mueller matrix. Two liquid-crystal variable retarders are used for controlling the input state of polarization, whereas the measurement of the state of polarization involves phase modulation with a single-pass photoelastic modulator, and Fourier analysis in two polarization channels. The setup is controlled by a computer, allowing for real-time measurement of the Mueller matrix. The method is tested on standard elements such as polarizers and quarter-wave plates, as well as on inhomogeneous particulate systems.