Tunable heteromorphic Bessel beam arrays enabled by multi-phase hybrid modulation in free space

Constructing Heteromorphic Bessel Beam (HBB) arrays in free space not only involves complex calculations and design but also presents a challenge for independently controlling the parameters of the HBBs within the array. We propose a composite phase structure incorporating an optical pen phase, a cross phase, a Bessel phase, and a vortex phase. Utilizing this composite phase enables the generation of complex HBB arrays within free space. Experimental results demonstrate that the shape, position, number, and size of the HBBs within the array can be independently tuned, and they maintain stable propagation over a distance of up to 2.10 mm. This method is simple and efficient, promising broad application prospects in fields such as particle trapping, optical tweezers, and optical communications.