Polarization‐Controlled Broadband Accelerating Beams Generation by Single Catenary‐Shaped Metasurface

Abstract Self‐accelerating beams have drawn enormous attentions in optics owing to their nondiffracting and self‐healing properties. Traditionally, the generation of such beams demands bulky devices and a long working distance, which impede the miniaturization of the optical system. Recent progresses in metasurfaces facilitate replacing cumbersome optical components by ultrathin and planar nano‐optical devices. Nevertheless, most of the existing approaches suffer from fixed trajectories, narrow operation bandwidth and low efficiency. Here, a methodology is proposed to generate self‐accelerating beams with arbitrary profiles by employing a generalized analysis based on geometric optics and interference theory. As a proof of the concept, single catenary‐shaped metasurface is utilized to generate the cubic phase shift, which leads to a reciprocal accelerating trajectory. The spatially continuous and spectrally dispersionless catenary nanoapertures show great advantages in terms of bandwidth and efficiency over discrete counterparts. The polarization‐controlled accelerating trajectories are demonstrated by both simulations and measured results. The proposed compact and efficient beam generators are believed to be promising for future on‐chip and integration applications.