Nazarova D.Sharlandjiev P.Berberova N.Blagoeva B.Stoykova E.Nedelchev L.2024-07-102024-07-102024-07-102024-07-102018-04-051742-65961742-658810.1088/1742-6596/992/1/012018SCOPUS_ID:85045752650https://rlib.uctm.edu/handle/123456789/466In this paper, we evaluate the optical response of a stack of two diffraction gratings of equal one-dimensional periodicity. The first one is a surface-relief grating structure; the second, a volume polarization grating. This model is based on our experimental results from polarization holographic recordings in azopolymer films. We used films of commercially available azopolymer (poly[1-[4-(3-carboxy-4-hydroxyphenylazo) benzenesulfonamido]-1,2-ethanediyl, sodium salt]), shortly denoted as PAZO. During the recording process, a polarization grating in the volume of the material and a relief grating on the film surface are formed simultaneously. In order to evaluate numerically the optical response of this ``hybrid`` diffraction structure, we used the rigorous coupled-wave approach (RCWA). It yields stable numerical solutions of Maxwell's vector equations using the algebraic eigenvalue method.enConference Paper