A tunable broadband terahertz MoS₂ absorber using series-parallel hybrid network design

Area of Science:

• Materials Science
• Nanotechnology
• Electromagnetics

Background:

• Broadband absorbers are crucial for applications like radar stealth and terahertz imaging.
• Existing multilayered absorbers are often complex and difficult to fabricate.
• Tunable and single-layered absorbers with broadband characteristics are highly desirable.

Purpose of the Study:

• To propose a novel method for designing a tunable, single-layered broadband absorber.
• To enhance absorber performance using frequency-selective surface patterns and a series-parallel hybrid network.
• To investigate the tunability and angular/polarization dependence of the proposed absorber.

Main Methods:

• Design of a broadband absorber utilizing a series-parallel hybrid network.
• Integration of frequency-selective surface patterns for performance enhancement.
• Utilizing a single-layered molybdenum disulfide (MoS2) material.
• Analysis of absorption, bandwidth, tunability via bias voltage, and angular/polarization characteristics.

Main Results:

• Achieved broadband absorption exceeding 90% from 0.84 to 2.34 THz (94.3% relative absorption bandwidth).
• Demonstrated tunable absorption from 90% down to 10% using applied bias voltage.
• Confirmed polarization insensitivity within 60° (TM) and 50° (TE) incidence angles.
• Showcased the impact of MoS2 layer types and surface fluctuations on absorber properties.

Conclusions:

• The proposed series-parallel hybrid network enables a single-layered MoS2 absorber with excellent broadband characteristics.
• The tunable nature and simplified structure significantly broaden the applicability of single-layered absorbers.
• This design offers a competitive alternative to complex multilayered absorbers for terahertz applications.