Switchable Tri-Functional Terahertz Metamaterial Integrated with Vanadium Dioxide and Photosensitive Silicon

Area of Science:

• Condensed Matter Physics
• Materials Science
• Electromagnetics

Background:

• Terahertz (THz) technology requires advanced metamaterials for diverse applications.
• Vanadium dioxide (VO2) exhibits a phase transition, enabling tunable electromagnetic properties.
• Photosensitive silicon offers a pathway for active control of metamaterial responses.

Purpose of the Study:

• To theoretically and numerically investigate a novel switchable tri-functional terahertz metamaterial.
• To demonstrate selective absorption, broadband polarization conversion, and dual-band asymmetric transmission.
• To explore active modulation of device performance using photosensitive silicon.

Main Methods:

• Theoretical modeling and numerical simulations of the proposed metamaterial structure.
• Analysis of electromagnetic response based on the phase transition of VO2 (metallic and insulating states).
• Investigation of the impact of photosensitive silicon conductivity on device functionality.

Main Results:

• Achieved selective perfect absorption for x-polarized waves at 2.84 THz when VO2 is metallic.
• Demonstrated broadband linear-to-linear polarization conversion (>99% ratio from 1.07 to 4.29 THz) when VO2 is insulating.
• Observed simultaneous dual-band asymmetric transmission linked to polarization conversion, with active modulation capabilities.

Conclusions:

• The proposed metamaterial exhibits switchable tri-functionality (absorption, polarization conversion, AT) driven by VO2 phase transition.
• Active control over polarization conversion efficiency and asymmetric transmission is achievable via photosensitive silicon.
• This work presents a promising platform for developing reconfigurable and multifunctional terahertz devices.