Opt Express. 2023 Apr 24;31(9):13739-13750. doi: 10.1364/OE.483593.
Traditional grating lenses can accumulate phase for adjusting wavefronts, and plasmonic resonances can be excited in metasurfaces with discrete structures for optical field modulation. Diffractive and plasma optics have been developing in parallel, with easy processing, small size, and dynamic control advantages. Due to theoretical hybridization, structural design can combine advantages and show great potential value. Changing the shape and size of the flat metasurface can easily produce light field reflections, but changes in height are rarely cross-explored. We propose a graded metasurface with a single-structure periodic arrangement, which can mix the effects of plasmonic resonance and grating diffraction. As for solvents of different polarities, strong polarization-dependent beam reflections are produced, enabling versatile beam convergence and deflection. Dielectric/metal nanostructures with selective hydrophobic/hydrophilic properties can be arranged by the structural material specification to selectively settle the location of the solution in a liquid environment. Furthermore, the wetted metasurface is actively triggered to achieve spectral control and initiate polarization-dependent beam steering in the broadband visible light region. Actively reconfigurable polarization-dependent beam steering has potential applications in tunable optical displays, directional emission, beam manipulation and processing, and sensing technologies.
传统的光栅透镜可以积累相位以调整波前，而具有离散结构的等离子体共振可以在超表面中被激发以进行光场调制。衍射和等离子体光学一直在平行发展，具有易于加工、尺寸小和动态控制的优势。由于理论上的杂交，结构设计可以结合优势并显示出巨大的潜在价值。改变平面超表面的形状和大小可以很容易地产生光场反射，但很少探索高度的变化。我们提出了一种具有单一结构周期性排列的渐变超表面，可以混合等离子体共振和光栅衍射的效果。对于不同极性的溶剂，会产生强烈的偏振相关光束反射，从而实现灵活的光束会聚和偏转。具有选择性疏水/亲水特性的介电/金属纳米结构可以通过结构材料规范进行布置，以选择性地确定溶液在液体环境中的位置。此外，润湿的超表面可以被主动触发，以在宽带可见光区域实现光谱控制和偏振相关光束转向。主动可重构的偏振相关光束转向在可调谐光学显示器、定向发射、光束操纵和处理以及传感技术中有潜在的应用。
