Abstract. An objective analysis is carried out of the matricial models representing the polarimetric properties of light and material media leading to the identification and definition of their corresponding physical quantities, using the concept of the coherency matrix. For light, cases of homogeneous and inhomogeneous wavefront are analyzed, and a model for 3D polarimetric purity is constructed. For linear passive material media, a general model is developed on the basis that any physically realizable linear transformation of Stokes vectors is equivalent to an ensemble average of passive, deterministic nondepolarizing transformations. Through this framework, the relevant physical quantities, including indices of polarimetric purity, are identified and decoupled. Some decompositions of the whole system into a set of well-defined components are considered, as well as techniques for isolating the unknown components by means of new procedures for subtracting coherency matrices. These results and methods constitute a powerful tool for analyzing and exploiting experimental and industrial polarimetry. Some particular application examples are indicated.

No abstract

A complete and minimum set of necessary and sufficient conditions for a real 4 x 4 matrix to be a physical Mueller matrix is obtained. An additional condition is presented to complete the set of known conditions, namely, the four conditions obtained from the nonnegativity of the eigenvalues of the Hermitian matrix H associated with a Mueller matrix M and the transmittance condition. Using the properties of H, a demonstration is also presented of Tr(M(T)M) = 4m(2)00 as being a necessary and sufficient condition for a physical Mueller matrix to be a pure Mueller matrix.

No abstract

From an appropriate parameterization of the three-dimensional (3D) coherency matrix R, that characterizes the second-order, classical states of polarization, the coherency matrices are classified and interpreted in terms of incoherent decompositions. The relevant physical quantities derived from R, as the intensity, the degree of polarimetric purity, the indices of polarimetric purity, the angular momentum, the degree of directionality and the degree of linear polarization are identified and interpreted on the light of the case study performed. The information provided by R about the direction of propagation is clarified and it is found that coherency matrices with rank 2  R , does not always represent states with a well-defined direction of propagation. Moreover, it is demonstrated the existence of 3D mixed states that cannot be decomposed into a superposition of a pure state, a 2D unpolarized state, and a 3D unpolarized state. Appropriate representation and interpretation for all the different types of 3D coherency matrices is provided through physical consistent criteria. Under the approach proposed, the conventional two-dimensional model arises naturally.