Flexible Manipulation of Bessel-Like Beams with a Reconfigurable Metasurface

Bessel beams have attracted considerable interest due to their intriguing nondiffraction and self-healing properties. Such beam can be generated by conventional devices that are more or less subjected to issues of low efficiency, complex manufacturing, and bulky size. Here, an electronically engineered reflective metasurface is designed to generate and flexibly manipulate Bessel-like beams over a broad frequency range in the microwave regime. Due to the dynamic resonance feature of the metasurface, the phase profile can be easily adjusted for different applications. The nondiffraction feature is illustrated by analyzing several configurations with different nondiffraction area of the Bessel-like beam, while the self-healing property is verified by placing a metallic obstacle in the propagation path. The dynamic control of functional frequency and propagation direction of Bessel-like beams is realized by controlling the external DC bias voltage applied to the metasurface. Experimental validation of the aforementioned features is perfectly consistent with numerical simulations. Owing to the flexible control, broad bandwidth, and high-efficiency properties, the proposed Bessel-like beam generator suggests potential applications in microwave domain such as focusing, wireless power transmission, and other complex demands such as beam steering.