Converting surface plasmon to spatial Airy beam by graded grating on metal surface.

A well-developed phase modulation method is utilized to design a nanogroove grating for a desired diffraction process, which gives rise to the conversion of a surface plasmon wave to an Airy-like radiation beam. Experiments and simulations revealed the unique characteristics of the generated Airy-like beam, such as nonspreading, self-bending, and self-healing. Our result confirms the validation of the diffraction strategy for beam engineering in conversions and possibly indicates wider applications in broader areas.