Thermally tunable THz modulator based on a metasurface with VO₂

Area of Science:

• Optics and Photonics
• Materials Science
• Electromagnetism

Background:

• Terahertz (THz) technology requires efficient modulation and sensing capabilities.
• Vanadium dioxide (VO2) exhibits a phase transition between metallic and insulating states, offering tunable electromagnetic properties.
• Metasurfaces provide a platform for manipulating electromagnetic waves with subwavelength structures.

Purpose of the Study:

• To introduce a novel
• C
• -shaped metasurface modulator utilizing the phase transition of VO2.
• To investigate the tunability of resonant frequencies and modulation performance.
• To evaluate the temperature-sensing capabilities of the proposed device.

Main Methods:

• Fabrication of a
• C
• -shaped metasurface incorporating VO2.
• Characterization of the metasurface's optical and electrical properties across a temperature range.
• Electromagnetic simulations to analyze resonance modes and frequency tunability.

Main Results:

• The metasurface exhibits tunable resonant frequencies controlled by structural geometry and VO2 phase transition.
• A high modulation depth exceeding 50% was achieved, with a maximum of 97% at 0.405 THz.
• Significant temperature sensitivity of 0.046/°C was observed in the 50-74°C range.

Conclusions:

• The proposed
• C
• -shaped VO2 metasurface modulator demonstrates excellent THz modulation performance and temperature-sensing capabilities.
• The device shows potential for applications in smart windows, sensors, and future 6G communication systems.
• This work contributes to the advancement of practical and high-performance THz functional devices.