Fig. 1
From: Phyllotaxis-inspired nanosieves with multiplexed orbital angular momentum
Free-space phyllotaxis-inspired vortex nanosieve. a A “Golden-ratio” phyllotaxis pattern producing “Fibonacci” OAM series inspires us to design phyllotaxis-alike vortex nanosieves. In the Fresnel region, the diffractive pattern of a Vogel spiral nanosieve with 936 florets is simulated and mode coefficients are calculated. The corresponding results reveal the link between phyllotaxis patterns and optical vortices, thus inspiring us to design phyllotaxis-alike vortex nanosieves. b Free-space phyllotaxis-inspired vortex nanosieve generating four different on-axis optical vortices simultaneously in free-space. Left panel: The red, purple, green, and blue solid circles denote the four different motifs concealed in the free-space phyllotaxis-inspired vortex nanosieve structure. Right panel: The four different sets of concealed spirals and their relevant simulated Fresnel diffraction intensity profiles