Geometric metasurface for simultaneously detecting polarization state and incident angle.

Area of Science:

• Optics and Photonics
• Electromagnetism
• Materials Science

Background:

• Electromagnetic (EM) waves possess fundamental properties like polarization and incident angle, crucial for information processing.
• Current methods for detecting EM wave properties are often limited to a single dimension, hindering comprehensive analysis.
• Terahertz (THz) wave applications are expanding, necessitating advanced detection techniques.

Purpose of the Study:

• To propose and experimentally demonstrate a novel approach for simultaneous detection of polarization and incident angle of THz waves.
• To overcome the limitations of existing methods that can only detect one property at a time.
• To leverage geometric metasurfaces for multi-dimensional THz wave characterization.

Main Methods:

• Utilizing a geometric metasurface platform to encode a quadratic phase profile.
• Transforming rotational symmetry of off-axis incident light into translational symmetry.
• Achieving a wide field of view (WFOV) single focal point for simultaneous detection.

Main Results:

• Demonstrated simultaneous detection of both polarization and incident angle of THz waves.
• Incident angle determined by translational distance of the focal point.
• Polarization state reconstructed using Stokes parameters from focal point intensity and phase.

Conclusions:

• The proposed geometric metasurface enables simultaneous multi-dimensional detection of THz wave properties.
• This approach offers a new pathway for developing multifunctional THz devices and integrated systems.
• The method enhances the capabilities for analyzing and utilizing THz wave information.