The general equation for polarized neutron reflectivity is derived and presented in an invariant vector form that is independent of the selection of a specific coordinate system. Using this representation the reflectivity may easily and thoroughly be analyzed for arbitrary orientation of the sample, the incident beam polarization, and the direction of polarization analysis. It is shown that the complete information that can be extracted from experimental data by a detailed polarization analysis is given by the following quantities: the two complex eigenvalues of the reflectance matrix and a complex vector defining a direction that coincides with the direction of the magnetizations in a collinear magnetization arrangement, but depends on the momentum transfer in the general noncollinear case. A supermatrix formalism is developed and illustrated that allows us to calculate these parameters for multilayers with arbitrary mutual orientation of the magnetizations in individual layers. Our approach opens an alternative way to a complete and unambiguous characterization of artificial magnetic structures of high complexity.

• Received 19 May 1999

DOI:https://doi.org/10.1103/PhysRevB.60.16073