Dual-Wavelength Polarization Modulated Multifunctional Metasurface

传统单一自由度的超构表面难以实现复杂的光场调控，而多功能集成器件的开发则为突破这一瓶颈提供了可能。本文提出了一种基于几何相位调控的双波长多功能太赫兹超构表面，通过亚波长单元结构的旋转角度设计，实现了跨波段偏振态与三维光场的协同操控。超表面在0.52太赫兹表现为偏振分束器，而在0.6太赫兹表现为涡旋发射器。改变超表面相位分布，进一步实现了双波长偏振相关的全息加密功能。仿真验证了器件在横向/纵向光场调控、多维度信息编码方面的灵活性，为集成光子器件、光学加密通信及智能成像系统提供了新的设计方法。Conventional single-degree-of-freedom metasurfaces face limitations in achieving complex optical field manipulation, while the development of multifunctional integrated devices offers a breakthrough pathway. This study proposes a dual-wavelength multifunctional terahertz metasurface based on geometric phase modulation. Through rotational angle design of subwavelength unit structures, the metasurface enables synergistic control of polarization states and three-dimensional optical fields across distinct frequency bands. Specifically, the device functions as a polarization beam splitter at 0.52 THz and switches to a vortex generator mode at 0.6 THz. By reconfiguring the phase distribution, it further realizes dual-wavelength polarization-dependent holographic encryption functionality. Numerical simulations validate the device’s versatility in transverse/longitudinal optical field manipulation and multidimensional information encoding, providing novel design methodologies for integrated photonic devices, secure optical communication systems, and intelligent imaging architectures.