Tunable and switchable multi-functional terahertz metamaterials based on a hybrid vanadium dioxide-graphene...

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Terahertz (THz) metamaterials offer unique electromagnetic properties.
• Achieving tunable and multi-functional devices remains a key challenge.
• Hybrid structures integrating phase-change materials and 2D materials show promise.

Purpose of the Study:

• To propose and demonstrate an actively tunable and switchable multi-functional THz metamaterial device.
• To integrate vanadium dioxide (VO2) and graphene for versatile THz applications.
• To achieve switchable asymmetric transmission and polarization conversion.

Main Methods:

• Fabrication of a hybrid VO2-graphene metamaterial structure.
• Utilizing the phase transition of VO2 to control device functionality.
• Investigating terahertz response through simulations and/or experiments.

Main Results:

• Achieved switchable asymmetric transmission (AT) up to 0.34 in the insulating state of VO2.
• Demonstrated simultaneous linear-to-linear and linear-to-circular polarization conversion in the conducting state.
• Obtained high polarization conversion ratios (>96.5%) and efficient wave-plate functionalities at specific THz frequencies.
• Showcased active control via VO2 phase transition and graphene's Fermi energy.

Conclusions:

• The proposed hybrid VO2-graphene metamaterial device exhibits multi-functionality and active tunability in the THz region.
• This work presents a new pathway for developing advanced, reconfigurable THz optical components.
• The design holds potential for applications in THz sensing, imaging, and communication systems.