Metasurface-Based Wide Amplitude Modulated Airy Beams for Particle Manipulation

Airy beams with specific amplitude and phase distributions are intriguing due to their self-reconstruction, nondiffraction, and self-accelerating properties. Previously most metasurfaces took only modulating phase for the generation of Airy beams, resulting in a certain distance for beam forming, which hampers their applications in optical manipulation. In this work, we reported a method to generate 2D/array Airy beams by using phase-amplitude-modulated metasurfaces and investigated their particle manipulation. The designed metasurfaces have an ultra-wide amplitude modulation range with a transmittance from 9% to 92% in order that the generated 2D Airy beams can be formed immediately after a short propagation distance. The self-healing property of the generated 2D Airy beams was demonstrated. Quantitative analysis of the optical forces shows that the generated 2D Airy beams can stably trap and drive particles even being obstructed. In addition, we introduced a strategy to build array Airy beams by superposing four rotated 2D ones and demonstrated their self-healing property. Our work advances the application of Airy beams in optical tweezers and highlights their potential in optical, biological, and atmospheric science.