Fig. 3: A super metalens with 200 focal points located along a single-cycle 3D cylindrical helix.

a The schematic diagram of super metalens M₂ with focal points on a continuous single-cycle 3D cylindrical helix trajectory with a constant pitch and a constant radius. There are 200 operating wavelengths ranging from 501 to 700 nm with a step size of 1 nm. The longitudinal separation is equal to 2 µm, which makes the total longitudinal length of the cylindrical helix equal to 398 µm, spanning from 302 to 700 µm. b The polarization rotation angles and operating wavelengths of the selected focal points. c Intensity distributions of the selected focal points (1st, 26th, 51st, 101st,151st, and 200th) at the corresponding operating wavelengths (501, 526, 551, 601, 651, and 700 nm) and longitudinal distances (302, 352, 402, 502, 602, and 700 µm). The direction of the analyzer (solid yellow arrow) is always perpendicular to the polarization direction of the incident light beam (dashed white arrow). The dashed yellow curves with arrows represent the mapped trajectory by the focal points on the single-cycle 3D cylindrical helix with a constant radius. The solid white arrows with dotted yellow circles represent the initial polarization rotation angles (at β = 0°). The regions of the corresponding focal points are highlighted with dotted yellow circles