Addressable metasurfaces for dynamic holography and optical information encryption

TL;DR

This paper introduces a dynamic metasurface platform that uses chemically controlled pixels for advanced holography and encryption, enabling secure, customizable optical data storage and transmission.

Contribution

It presents a novel chemically tunable metasurface system for dynamic holography and encryption, expanding beyond static metasurface applications.

Findings

Demonstrated chemically controlled, addressable pixels for dynamic holography

Achieved multiplexed encryption using multiple keys including light helicity and chemical states

Enabled secure, customizable optical information encoding with high security levels

Abstract

Metasurfaces enable manipulation of light propagation at an unprecedented level, benefitting from a number of merits unavailable to conventional optical elements, such as ultracompactness, precise phase and polarization control at deep subwavelength scale, and multifunctionalities. Recent progress in this field has witnessed a plethora of functional metasurfaces, ranging from lenses and vortex beam generation to holography. However, research endeavors have been mainly devoted to static devices, exploiting only a glimpse of opportunities that metasurfaces can offer. We demonstrate a dynamic metasurface platform, which allows independent manipulation of addressable subwavelength pixels at visible frequencies through controlled chemical reactions. In particular, we create dynamic metasurface holograms for advanced optical information processing and encryption. Plasmonic nanorods tailored to exhibit hierarchical reaction kinetics upon hydrogenation/dehydrogenation constitute addressable pixels in multiplexed metasurfaces. The helicity of light, hydrogen, oxygen, and reaction duration serve as multiple keys to encrypt the metasurfaces. One single metasurface can be deciphered into manifold messages with customized keys, featuring a compact data storage scheme as well as a high level of information security. Our work suggests a novel route to protect and transmit classified data, where highly restricted access of information is imposed.