Ptychography retrieval of fully polarized holograms from geometric-phase metasurfaces

Qinghua Song,Arthur Baroni,Patrice Genevet,Patrick Ferrand,Stéphane Vézian,Peinan Ni,Samira Khadir,Philippe De Mierry,Sébastien Chenot,Virginie Brandli,Benjamin Damilano,Rajath Sawant

doi:10.1038/s41467-020-16437-9

Abstract

Controlling light properties with diffractive planar elements requires full-polarization channels and accurate reconstruction of optical signal for real applications. Here, we present a general method that enables wavefront shaping with arbitrary output polarization by encoding both phase and polarization information into pixelated metasurfaces. We apply this concept to convert an input plane wave with linear polarization to a holographic image with arbitrary spatial output polarization. A vectorial ptychography technique is introduced for mapping the Jones matrix to monitor the reconstructed metasurface output field and to compute the full polarization properties of the vectorial far field patterns, confirming that pixelated interfaces can deflect vectorial images to desired directions for accurate targeting and wavefront shaping. Multiplexing pixelated deflectors that address different polarizations have been integrated into a shared aperture to display several arbitrary polarized images, leading to promising new applications in vector beam generation, full color display and augmented/virtual reality imaging.

Highlights

Controlling light properties with diffractive planar elements requires full-polarization channels and accurate reconstruction of optical signal for real applications
Ultrathin and planar optical elements composed of subwavelength scale elements capable of encoding amplitude, phase and polarization information have been used to manipulate the wavefront of light[1,2,3,4,5,6,7], enabling holographic projection[8,9,10], offering new avenues for lightweight virtual and augmented reality (VR/AR) headsets
Relying on PB phase information, any birefringent dielectric building block with an orientation angle of φ can perform the conversion jLi ! ei2φjRi and jRi ! eÀi2φjLi, i.e., the LCP and RCP beams are transformed to opposite spin with a PB phase of 2φ and −2φ, respectively

Summary

Introduction

Controlling light properties with diffractive planar elements requires full-polarization channels and accurate reconstruction of optical signal for real applications. Ultrathin and planar optical elements composed of subwavelength scale elements capable of encoding amplitude, phase and polarization information have been used to manipulate the wavefront of light[1,2,3,4,5,6,7], enabling holographic projection[8,9,10], offering new avenues for lightweight VR/AR headsets Such artificial interfaces, dubbed metasurfaces and meta-holograms are based on resonant structures[11,12] and/or geometry phase (or Pancharatnam–Berry (PB) phase)[13,14,15] to cover a full 2π phase range for encoding the arbitrary holographic phase profile. A multidirectional meta-hologram is achieved for multiplexing polarization channels in different directions

Methods

Results

Conclusion