An ultra-broadband multilayered graphene absorber

Area of Science:

• Materials Science
• Optics and Photonics
• Condensed Matter Physics

Background:

• Terahertz (THz) frequency applications require efficient absorbers.
• Existing metallic and graphene absorbers have limited operational bandwidths.
• Developing broadband absorbers is crucial for advancing THz technologies.

Purpose of the Study:

• To propose and analyze an ultra-broadband multilayered graphene absorber for THz frequencies.
• To investigate the mechanisms enabling ultra-broadband absorption.
• To demonstrate enhanced absorption bandwidth using patterned graphene layers.

Main Methods:

• Asymmetric patterning of graphene layers to support higher-order surface plasmon modes.
• Stacking of patterned graphene layers biased at different gate voltages with dielectric substrates.
• Increasing graphene's damping factor by reducing electron mobility to 1000 cm²/Vs.

Main Results:

• Achieved ultra-broadband operation up to 7 THz with 90% absorption using only three graphene layers.
• Demonstrated electromagnetically induced absorption through destructive interference of plasmon modes.
• Observed polarization dependence in the absorber's performance.

Conclusions:

• The proposed multilayered graphene absorber offers a significant advancement in THz absorption bandwidth.
• The design overcomes limitations of conventional absorbers, enabling wider THz applications.
• This approach provides a pathway for developing next-generation THz devices.