RESUMO
Birefringence of elliptical polarization eigenmodes can be conceptualized as a composite system comprising two distinct media: one with linear polarization eigenmodes and the other with circular polarization eigenmodes. However, the practical realization of such a system often involves the combination of two birefringent quarter-wave plates (QWPs). In this study, our objective is to characterize the variable retardation and variable elliptical polarization eigenmodes exhibited by a biplate consisting of two quarter-wave plates. Additionally, we aim to analyze the geometric properties of the transformation of one state of polarization on the Poincaré sphere, employing the emerging state's curve. This curve corresponds to the intersection between the Poincaré sphere and a cone. The outcomes of our study are presented as a function of the angle between the fast axes of the two QWPs. The findings have the potential to contribute to the configuration of q-plates and facilitate the development of quantum communication protocols.
RESUMO
Characterization of the birefringence of materials offers the opportunity to develop applications and elements to manipulate the polarization of light. We propose a new method for characterizing the effective phase retardation based on the linear birefringent law. The proposed method is flexible and easy to implement; it also determines the retardation introduced by a linear birefringent as from an input polarization state and a specific output state generated by the rotated material. The method is evaluated experimentally by characterizing the birefringence of cellophane samples.
