Arbitrary polarization conversion and phase control using full- parameter AA-phase metasurface

Arbitrary polarization states represent the most comprehensive information of electromagnetic (EM) wave, and variable polarization channels of EM waves can be widely utilized in target detection. Here, a novel strategy is proposed for arbitrary polarization generation and wavefront control with Aharonov-Anandan (AA) and Pancharatnam-Berry (PB) phases. Based on theoretical analysis, it is indicated that comprehensive Jones matrices of AA phase and PB phase enable precise and flexible control of polarization. To validate the feasibility of this matrix, two cases are considered. In case I, two orthogonal circularly polarized (CP) channels of a single metaatom are utilized to generate an arbitrary linear polarization (LP) state and to manipulate wavefront by combing aforementioned phases. In case II, co- and cross- polarization amplitude terms are decoupled by employing angular difference of two meta-atoms to manipulate ellipticity angle, while corresponding dual-channel phase difference is utilized to control azimuth angle. Consequently, left- or right-handed CP wave can be converted into arbitrary polarized wave with a controllable wavefront, leveraging its amplitude and phase through both co- and cross-polarized channels. For demonstration and potential applications, two meta-devices were realized, and excellent beam deflection and bifocal focusing at arbitrary polarization under illumination of LP and CP waves verifies our concept. Our strategy sets a solid platform in implementing arbitrarily polarized EM devices.