Creating Wavelength-Selective Polarization Digital Numbers

Polarization and wavelength are two important properties of light for understanding optics. Engineered polarization and wavelength profiles have received considerable interest due to their unusual optical features and more degrees of freedom. However, to simultaneously control polarization and wavelengths, conventional methods suffer from big pixel size, complicated fabrication process, and limited levels in phase control. The unprecedented capability of metasurfaces in the light control has shown much promise to tackle these challenges. Polarization digital numbers with ten different wavelengths are proposed and experimentally realized. A geometric metasurface is used to simultaneously realize wavelength multiplexing, phase multiplexing, and polarization rotation, creating wavelength-selective polarization digital numbers. A deep learning approach is used to increase the identification accuracy of the digital numbers. The approach can simultaneously control wavelength and polarization, providing more design flexibility. This work may find applications in many fields such as virtual reality, image steganography, and anti-counterfeiting.

Automated summary

Polarization and wavelength are important properties of light. Engineered polarization and wavelength profiles have gained interest due to their unique optical features. Traditional methods for simultaneous polarization and wavelength control suffer from limitations, but metasurfaces offer promising solutions. This study proposes and realizes polarization digital numbers with ten different wavelengths, using a geometric metasurface for wavelength multiplexing, phase multiplexing, and polarization rotation. The use of deep learning enhances digital number identification accuracy. This work provides more design flexibility by simultaneously controlling wavelength and polarization, with potential applications in virtual reality, image steganography, and anti-counterfeiting.