The existing methods for the generation of arbitrary vector vortex beams often involve complex optical setups or intricate fabrication methods. In this Letter, we propose a novel, to the best of our knowledge, and simplified approach for the efficient generation of vector vortex beams using a polarization-multiplexed hologram fabricated on an azo-carbazole polymer using a simple double-exposure technique. The hologram generates a vector vortex beam when simply illuminated by a collimated beam and also allows for a seamless traversal across the entire higher-order Poincaré sphere (arbitrary vortex beam generation) just by modulating the polarization of an illuminating beam.

Ince–Gaussian beams, defined as a solution to a wave equation in elliptical coordinates, have shown great advantages in applications such as optical communication, optical trapping and optical computation. However, to ingress these applications, a compact and scalable method for generating these beams is required. Here, we present a simple method that satisfies the above requirement, and is capable of generating arbitrary Ince–Gaussian beams and their superposed states through a computer-generated hologram of size 1 mm², fabricated on an azocarbazole polymer film. Other structural beams that can be derived from the Ince–Gaussian beam were also successfully generated by changing the elliptical parameters of the Ince–Gaussian beam. The orthogonality relations between different Ince–Gaussian modes were investigated in order to verify applicability in an optical communication regime. The complete python source code for computing the Ince–Gaussian beams and their holograms are also provided.

Laguerre–Gaussian beams are structured light beams with a donut-shaped symmetric intensity profile and a helical phase profile. The beam profile is defined by a quantized parameter known as the mode number which extends to infinity. The availability of unbounded modes makes these beams a promising candidate for next-generation optical computing, and optical communication technologies. The symmetric intensity profile of a Laguerre–Gaussian beam can be made asymmetric through certain techniques and these beams are known by the term ‘asymmetric Laguerre–Gaussian beams’. Here, the asymmetricity adds another degree of freedom to the beam (apart from its mode number) which helps in encoding more information compared to a symmetric beam. However, in order to harness the benefits of all the available degrees of freedom, it is required to generate a large number of such beams in a multiplexed fashion. Here, we report the generation of such a large array of asymmetric Laguerre–Gaussian beams for the first time. Computer-generated holography and spatial multiplexing techniques were employed to generate a large array comprising of 12 × 16 = 192 asymmetric Laguerre–Gaussian beams with an arbitrary mode index and asymmetricity.

Vector holography has emerged as a promising technique that unlocks the polarization degree of freedom of light to be used for generating, storing, and reproducing information. Vector holograms with rewritable capabilities are desirable in applications such as optical computing, data storage, dynamic beam shaping, optical communication, etc. However, the development of materials for rewritable vector holography poses significant challenges. Materials such as photopolymers and metamaterials for vector holograms show good performance and long-term storage capabilities but do not possess rewritable capabilities. On the other hand azo-based polymers, azobenzene liquid crystals, and photorefractive polymers are rewritable but often fail to satisfy other requirements such as higher diffraction efficiency, faster response, stability, and long-term storage, etc., simultaneously. In this study, we have investigated the potentials of azo-carbazole copolymer film for vector holography applications by conducting a thorough study on its polarization recording/reconstruction characteristics, for the first time. We found that the material exhibits a higher diffraction efficiency, reaching up to 85%, with good stability. The recording requires only a short exposure of 5 seconds, using laser power of a few milliwatts/cm². Our findings indicate that the proposed azo-carbazole polymer material holds great potential for evolving into the ‘rewritable vector holography recording material’ for the future, and is capable of advancing the field of vector holography and related applications.

In this study, we have demonstrated diverse applications of high-density polarization multiplexed holograms in an azo-carbazole polymer film. We investigate three distinct multiplexing methods, namely i) hybrid polarization-angular multiplexing for high-density data storage, ii) hybrid spatial-polarization multiplexing for a dynamic display, and iii) hybrid polarization-depth multiplexing for depth selective 3D display. Up to 24 images were successfully recorded and then retrieved individually from a single hologram without any cross-talk, using the first multiplexing scheme. Similarly, by employing the second multiplexing scheme, six new images were composed (reconstructed) from a hologram recorded with elemental patterns. Finally, images that can be selectively reconstructed at different depths have been demonstrated using the third multiplexing scheme. In this paper, up to three data recordings at one position in the thin azo-carbazole polymer film are demonstrated for the first time to the best of our knowledge. Our findings underscore the suitability of azo-carbazole copolymer-based composite films for various applications, spanning data storage and display technologies.