An Angle- and Polarization-Selective Dual-Wavelength Narrowband Thermal Emitter for Infrared Multilevel Encryption.

Area of Science:

• Optics and Photonics
• Information Security
• Materials Science

Background:

• The rapid expansion of digital data necessitates robust information security solutions.
• Current digital encryption methods are vulnerable to interception and leakage during data transmission.
• Combining digital algorithms with physical keys is a promising approach to enhance security.

Purpose of the Study:

• To develop an angle- and polarization-selective dual-wavelength long-wavelength infrared narrowband thermal emitter.
• To apply this emitter for advanced infrared encryption-decryption applications.
• To create a multilevel cryptographic communication system leveraging the thermal emitter.

Main Methods:

• Design and fabrication of a thermal emitter using epsilon-near-zero material on a metallic layer.
• Excitation of Berreman mode and asymmetric Fabry-Pérot resonance.
• Numerical simulations and transfer matrix method for optical response analysis.
• Experimental validation of simulated results.
• Development of a multilevel cryptographic communication system.

Main Results:

• The thermal emitter exhibits angle- and polarization-selective dual-wavelength narrowband emission in the long-wavelength infrared spectrum.
• Simulated optical responses show excellent agreement with experimental findings.
• A functional multilevel cryptographic communication system was successfully developed and demonstrated.
• The system utilizes the thermal emitter's imaging results as a physical-layer key for secure encryption and decryption.

Conclusions:

• The proposed thermal emitter provides a novel physical-layer key for highly efficient information encryption and decryption.
• This technology enhances information security by integrating optical properties with cryptographic principles.
• The developed system offers a robust solution for secure communication in infrared applications.
• These thermal emitters are expected to enable advancements in various information encryption devices.