High-efficiency complex beam generation utilizing a minimalist 1-bit phase coding metasurface

Metasurfaces, as artificial structures, have shown their high capacity to arbitrarily tailor electromagnetic wavefronts. Here, a minimalist 1-bit phase coding metasurface with “0” and “1” states is proposed for high-efficiency complex beam generation. The elementary unit cell, insensitive to the polarization of the incident wave, is arrayed in a hexagonal lattice and can be further exploited in any metasurface for any functionality. This minimalist metasurface, with only 50% of its surface covered with metallic patterns, can achieve a more accurate response manipulation. Three complex beams, including zeroth-order Bessel beam, vortex beam, and Airy beam, are achieved for validation with a high efficiency of over 78.5%. Both simulations and measurements are performed in the frequency band ranging from 11 GHz to 13 GHz. This minimalist metasurface shows high efficiency for potential applications in wireless communications, cognitive radars, and adaptive beamforming.