A Flat-Lensed Spiral Phase Plate Based on Phase-Shifting Surface for Generation of Millimeter-Wave OAM Beam

Abstract
A multilayer phase-shifting-surface-based flat plate is designed to offer a combination of lens and spiral phase plate (SPP) for orbital angular momentum (OAM) beam generation and convergence at 60 GHz. The proposed design consists of a series of phase-shift unit cells to control the emergent phase and form a flat lens for the purpose of beam focusing. The results of simulation and experiment verify that the OAM beam with small divergence angle can be achieved.
Funding Information
  • National Basic Research Program of China (2014CB340005, 2014CB340001)
  • National Natural Science Foundation of China (61371030)