Metasurfaces are two-dimensional nanoantenna arrays that can control the propagation of light at will. In particular, plasmonic metasurfaces feature ultrathin thicknesses, ease of fabrication, field confinement beyond the diffraction limit, superior nonlinear properties, and ultrafast performances. However, the technological relevance of plasmonic metasurfaces operating in the transmission mode at optical frequencies is questionable due to their limited efficiency. The state-of-the-art efficiency of geometric plasmonic metasurfaces at visible and near-infrared frequencies, for example, is ≤10%. Here, we report a multipole-interference-based transmission-type geometric plasmonic metasurface with a polarization conversion efficiency that reaches 42.3% at 744 nm, over 400% increase over the state of the art. The efficiency is augmented by breaking the scattering symmetry due to simultaneously approaching the generalized Kerker condition for two orthogonal polarizations. In addition, the design of the metasurface proposed in this study introduces an air gap between the antennas and the surrounding media that confines the field within the gap, which mitigates the crosstalk between meta-atoms and minimizes metallic absorption. The proposed metasurface is broadband, versatile, easy to fabricate, and highly tolerant to fabrication errors. We highlight the technological relevance of our plasmonic metasurface by demonstrating a transmission-type beam deflector and hologram with record efficiencies.

超表面是二维纳米天线阵列，可以随意控制光的传播。特别是，等离质子超表面具有超薄的厚度，易于制造，超出衍射极限的场限制，出色的非线性特性和超快性能。然而，由于其效率有限，在透射模式下以光频率工作的等离子体超颖表面的技术相关性值得怀疑。例如，在可见光和近红外频率下，几何等离子超表面的最新效率为≤10％。在这里，我们报告了一种基于多极干扰的透射型几何等离子超表面，其极化转换效率在744 nm处达到42.3％，比现有技术提高了400％以上。通过同时接近两个正交极化的广义Kerker条件，打破了散射对称性，从而提高了效率。此外，这项研究提出的超颖表面的设计在天线和周围介质之间引入了一个气隙，将气隙限制在该气隙内，从而减轻了亚原子之间的串扰并使金属吸收最小化。拟议的超颖表面具有宽带性，用途广泛，易于制造且高度可容忍制造错误的特点。通过展示具有记录效率的透射型光束偏转器和全息图，我们突出了等离子超颖表面的技术相关性。这项研究提出的超颖表面的设计在天线和周围介质之间引入了一个气隙，将气隙限制在该间隙内，从而减轻了亚原子之间的串扰，并使金属吸收最小化。拟议的超颖表面具有宽带性，用途广泛，易于制造且高度可容忍制造错误的特点。通过展示具有记录效率的透射型光束偏转器和全息图，我们突出了等离子超颖表面的技术相关性。这项研究提出的超颖表面的设计在天线和周围介质之间引入了一个气隙，将气隙限制在该间隙内，从而减轻了亚原子之间的串扰，并使金属吸收最小化。拟议的超颖表面具有宽带性，用途广泛，易于制造且高度可容忍制造错误的特点。通过展示具有记录效率的透射型光束偏转器和全息图，我们突出了等离子超颖表面的技术相关性。