Flexible terahertz phase shifter for optically controlled polydimethylsiloxane-vanadium dioxide composite film

Area of Science:

• Materials Science
• Optoelectronics
• Terahertz Technology

Background:

• Precise control of terahertz (THz) phase shift is crucial for THz modulation research.
• Flexible materials offer new possibilities for advanced optical devices.

Purpose of the Study:

• To investigate optical control of THz phase shift modulation in a flexible polydimethylsiloxane (PDMS)-vanadium dioxide (VO2) composite material.
• To evaluate the modulation performance and stability of the PDMS-VO2 material for THz applications.

Main Methods:

• Utilized terahertz time-domain spectroscopy (THz-TDS) to study phase shift modulation.
• Employed an 808-nm continuous wave (CW) laser for optical pumping of the PDMS-VO2 material.
• Tested material stability through repeatability tests over 640 switching cycles.

Main Results:

• Achieved significant THz phase shift modulation in the 0.2-1.0 THz range.
• Observed a maximum phase shift of 0.27π rad at 1.0 THz with 5% VO2 mass fraction and 360 µm thickness.
• Maintained amplitude transmittance above 70% across the tested frequency range.
• Demonstrated good material stability and repeatability.

Conclusions:

• The PDMS-VO2 composite enables flexible and precise optical control of THz phase shift modulation.
• The material's properties are suitable for developing wearable THz modulators.
• This work presents a novel approach for advanced THz modulation technologies.