Proportional Phase Modulation Approach for Steering of Airy Beams

Airy beams, renowned for their nondiffracting and self-bending characteristics, hold great promise for terahertz (THz) applications, such as imaging, communication, and detection. However, controlling beam trajectories in the THz band has been challenging due to the complexity and high costs associated with traditional phase or amplitude modulation techniques, which often require intricate pixel-level control and result in significant losses from switching components. In this work, we introduce a novel and practical method for generating tunable Airy beams by simply proportionally adjusting the phase of a specially designed lens. This approach enables direct and precise control of the beam’s trajectory through straightforward proportional phase modulation, eliminating the need for complex modulation schemes and costly components. We fabricated three lens prototypes using high-precision 3-D printing technology to validate our method. Each lens transforms an incident plane wave into an Airy beam following a distinct parabolic trajectory determined by the proportional phase modulation. Experimental results confirm that our method can generate and control the trajectory of Airy beam. This solution may be applied to THz communication and beam manipulation, effectively addressing the challenges of trajectory control in the THz band.