Multifunctional reconfigurable terahertz metasurface based on vanadium dioxide phase transition: achieving broadband...

Area of Science:

• Metamaterials and Nanophotonics
• Terahertz (THz) Technology
• Condensed Matter Physics

Background:

• Metasurfaces offer unique electromagnetic properties.
• Vanadium dioxide (VO2) exhibits a tunable phase transition with significant electromagnetic implications.
• Efficient terahertz absorption and polarization conversion are crucial for various applications.

Purpose of the Study:

• To design and demonstrate a reconfigurable terahertz metasurface.
• To achieve ultra-wideband absorption and cross-polarization conversion.
• To leverage the phase transition of VO2 for tunable terahertz functionalities.

Main Methods:

• Fabrication of a terahertz metasurface incorporating VO2.
• Characterization of the metasurface's electromagnetic response in both metallic and insulating phases of VO2.
• Analysis of absorption efficiency, bandwidth, polarization conversion ratio (PCR), and angular stability.

Main Results:

• Achieved ultra-wideband absorption (97.6% relative bandwidth) in the metallic phase (3.25-9.45 THz) with wide-angle stability (0°-60°).
• Demonstrated efficient cross-polarization conversion (PCR > 90%) in the insulating phase (3.17-9.02 THz) for both x- and y-polarized waves.
• Showcased dynamic and continuous tunability of absorption based on the extent of VO2 phase transition.

Conclusions:

• The proposed VO2-based metasurface provides reconfigurable ultra-wideband absorption and cross-polarization conversion.
• The device exhibits excellent polarization insensitivity and wide-angle performance.
• Potential applications include terahertz dynamic stealth, high-speed communication, and high-contrast polarization imaging.