Recent progress on multidimensional metasurface holography

Multidimensional metasurface holography employs subwavelength meta-atoms to manipulate optical field parameters such as phase, amplitude, and polarization, enabling multi-channel information encoding and selective reconstruction in ultrathin devices. This capability offers a promising route towards highly integrated display technologies, optical information encryption, virtual reality (VR) and augmented reality (AR) systems. The key principle lies in constructing distinguishable multiplexing channels using degrees of freedom (DOFs), such as wavelength, polarization, incidence angle, orbital angular momentum (OAM), and dynamic tunability, which substantially enhances the information capacity of metasurface holographic devices. In this review, we summarize recent progress on multidimensional metasurface holography from four perspectives: electromagnetic modulation mechanisms, design algorithms, free-space integration, and on-chip integrated multiplexing schemes. We first introduce the commonly used electromagnetic modulation strategies, including Pancharatnam–Berry (PB) phase, propagation phase, resonant phase, detour phase, and Malus's law. We then review representative design algorithms, ranging from conventional iterative and global optimization methods to deep-learning-assisted forward prediction and inverse design. Subsequently, we carefully discuss recent advances in multidimensional metasurface holography based on two typical integration platforms: free-space and on-chip architectures. Finally, we outline the major challenges in energy efficiency, image quality, fabrication complexity, and dynamic tunability, and provide an outlook on future development directions.