Dynamic Antireflection and Reflectance Terahertz Modulator via Impedance Matching Using Composite Ge₂Sb₂Te₅/VO₂...

Area of Science:

• Materials Science
• Optics and Photonics
• Electrical Engineering

Background:

• Terahertz (THz) antireflection technologies face challenges with complex switching and fabrication.
• Existing THz modulators often require stringent conditions, limiting practical applications.

Purpose of the Study:

• To develop a novel THz wave amplitude modulation method using a VO2/GST composite phase-change material interface.
• To enable efficient switching control and multiangle reflection modulation for THz signals.
• To explore current-driven dynamic control for enhanced modulation flexibility.

Main Methods:

• Fabrication of a VO2/GST composite phase-change material interface.
• Optimization of the device manufacturing process for room-temperature antireflection performance.
• Experimental characterization of THz amplitude and reflection modulation performance across various angles and frequencies.

Main Results:

• Achieved an amplitude modulation depth of 89.5% with the composite phase-change interface.
• Demonstrated superior reflection modulation performance over a wide angular range (15°–45°).
• Observed a broad response bandwidth from 0.2 to 1.5 THz.

Conclusions:

• The VO2/GST composite structure provides efficient THz amplitude and reflection modulation with enhanced flexibility.
• The developed device offers new pathways for designing advanced THz modulation devices.
• This innovation supports the expansion of terahertz technology applications.