FIG. 1.

(a) Conceptual schematic diagram. Two independent amplitude profiles ∣U^±(x,y)∣ can be imposed on a pair of orthogonal input polarization states ${\overrightarrow{\alpha }}^{\pm }$ through the metasurface, and makes the output polarization states ${\overrightarrow{\beta }}^{\pm }$ flip handedness. The green, red, and blue wavy lines donate the input, output, and reflection of optical waves, respectively. (b) Schematic diagram of metasurface array. The amplitude controlled metasurface is formed by meta-molecules array. Each meta-molecule (blue dashed box) consists of multiplexed waveplate-like birefringent meta-atoms. The right bottom inset shows a scanning electron microscope image of the fabricated metasurface (Oblique view). (c-d) Perspective and top view of a meta-atom. The dimension (L, W) and orientation angle Θ of the meta-atom can be varied to respectively provide desired propagation phase and geometric phase.