Recent Advances in Geometric Phase Metasurfaces: Principles and Applications

The concept of geometric phase traversing numerous domains in physics and has been a continuous source of fascination and inspiration for researchers. Despite the extensive research surrounding geometric phase from decades, advances in technology continue to yield novel theories, innovative devices, and captivating applications, extending even to the realm of subwavelength scales. This review article provides a comprehensive exploration of geometric phase metasurfaces, delving into their design principles and categorizing them based on materials properties. In addition, multi-fold and reconfigurable metasurfaces based on geometric principle are further explored with their unique capabilities and potential impact on a diverse range of applications, including beam steering, lensing, polarization conversion, and holographic imaging. By examining the state-of-the-art in geometric phase metasurfaces, insights are aimed to offer into their current capabilities and limitations. Finally, the prospects and challenges are discussed that lie ahead for this promising field, paving the way for future advancements and innovations.