Controllable Polarization and Diffraction Modulated Multi-Functionality Based on Metasurface

摘要

Diffraction gratings are crucial optical elements in various optical systems, which can realize tailored diffraction energy distributions as well as phase modulations based on Fourier series. Meanwhile, the polarization gratings can produce arbitrarily specified polarization states on a set of desired diffraction orders for realizing polarimeter. However, simultaneously and independently tailoring the encoded phase profiles and polarization states in different diffraction orders has not been investigated previously. Here, a dielectric metasurface with the capability of generating different holographic images (generalized phase profiles) in different diffraction orders with controllable polarization states is proposed. Such functionality is achieved by applying the double-phase method into the metasurface design process for manipulating the complex amplitude distributions of two orthogonal polarization bases. Furthermore, in order to prove that the proposed design strategy is suitable to achieve complicated wavefront modulation in a straightforward and convenient manner, a vectorial holographic image with spatially continuous polarization distribution is also obtained without any iteration process. The proposed method may pave the way to achieve a variety of applications such as beam shaping, polarization imaging as well as multifunctional optical systems.