面向偏振成像的超构表面研究进展

图 1  基于等离激元结构和全电介质结构的超构表面。（a）基于GSP结构的全斯托克斯偏振测定光栅型超构表面[84]；（b）该光栅型超构表面由3组相位梯度不同的微纳结构阵列组成，可调控(x, y)、(a, b)、(l, r)正交偏振态[84]；（c）基于GSP结构的光栅型圆偏振分光超构表面[85]；（d）基于GSP的透镜型偏振分光超构表面[86]；（e）超构单元包含2种TiO2微纳结构，分别调控左旋和右旋偏振光[92]；（f）圆二色性甲虫外骨骼成像实验[92]；（g）超像元由分别会聚x，y，a，b，l，r偏振态的超构透镜组成[93]；（h）该超构表面可作为Hartmann-Shack波前传感器，径向偏振光的强度分布（左），解析得到的偏振轮廓图（右）[93]

Figure 1.  Metasurfaces based on plasmonic and all dielectric structures. (a) Metagrating based on a GSP structure for the determination of full Stokes parameters[84]; (b) The metagrating consists three kinds of micro-nano structure arrays with different phase gradients, which can manipulate orthogonal polarization states (x, y), (a, b), (l, r)[84]; (c) Circular polarization splitting GSP-based metagrating[85]; (d) Polarization splitting and focusing GSP-based metalens[86]; (e) Meta-atom includes two kinds of TiO2 nano-micro structures manipulating left-handed and right-handed circular polarization light, respectively; (f) Polarization image of the exoskeleton of a chiral beetle[92]; (g) Meta-pixel is composed of metalenses focusing x，y，a，b，l，r polarization states, respectively[93]; (h) The metasurface can be served as Hartmann-Shack wavefront sensor, intensity distribution of radially polarized beam (left), and calculated polarization profile (right)[93]