Metasurface-enabled polarization-encoded terahertz encryption via angular spectrum intensity modulation

Area of Science:

• Optics and Photonics
• Information Security
• Metamaterials

Background:

• Exponential growth in communication networks necessitates advanced information security solutions.
• Optical encryption is a promising physical-layer approach for securing data.
• Metasurface-based optical encryption offers unique modulation capabilities.

Purpose of the Study:

• To present a terahertz encryption framework using an image as an information carrier.
• To decouple information from physical hardware for flexible data transmission.
• To enhance security through polarization-dependent decoding.

Main Methods:

• Information encoding into a specific Optical Transfer Function (OTF) via a metasurface.
• Modulation of the carrier's angular spectrum using the metasurface.
• Implementation of polarization-dependent decoding for information retrieval.

Main Results:

• A terahertz encryption framework decoupling information from hardware was successfully demonstrated.
• The metasurface-based OTF enabled flexible data transmission and digital processing.
• Polarization-dependent decoding significantly reinforced security by confining retrieval to specific channels.

Conclusions:

• The proposed scheme offers a versatile and robust solution for terahertz encryption.
• This approach provides advantages over traditional metasurface-based encryption methods.
• The framework enhances information security in rapidly growing communication networks.