Liquid crystal-based wide-angle metasurface absorber with large frequency tunability and low voltage

Area of Science:

• Terahertz (THz) technology
• Metamaterials and Plasmonics
• Liquid Crystal Photonics

Background:

• Metasurface absorbers (MAs) are crucial for various applications, but achieving both wide-angle stability and large frequency tunability remains a challenge.
• Traditional liquid crystal-based metasurfaces often suffer from slow response times and limited tunability ranges.

Purpose of the Study:

• To introduce a novel tunable metasurface absorber (MA) utilizing a polymer network liquid crystal.
• To demonstrate enhanced frequency tunability and wide-angle stability compared to existing liquid crystal metasurfaces.
• To reduce the recovery time of liquid crystal-based tunable absorbers.

Main Methods:

• Design and fabrication of a metasurface absorber with specifically engineered unit cell patterns.
• Characterization of the absorber's performance under varying applied voltages (0-10 V).
• Measurement of absorption spectra, frequency tunability, angular stability, and recovery time.

Main Results:

• The proposed MA exhibits a maximum frequency tunability of 9.3%, tuning the absorption peak from 112.7 GHz to 102.2 GHz.
• Absorption remains above 90% for incident angles up to 60° for both transverse electric (TE) and transverse magnetic (TM) polarizations.
• The recovery time of the device was reduced by half compared to traditional liquid crystal metasurfaces.

Conclusions:

• The developed polymer network liquid crystal metasurface absorber offers significant advancements in frequency tunability and wide-angle stability.
• This design presents an efficient pathway for creating low-power consumption terahertz devices.
• The improved performance metrics pave the way for next-generation terahertz sensing and communication systems.