Tunable Transmissive Terahertz Linear Polarizer for Arbitrary Linear Incidence Based on Low-Dimensional Metamaterials

Area of Science:

• Optics and Photonics
• Materials Science
• Nanotechnology

Background:

• Metamaterials offer unique light manipulation capabilities.
• Controlling polarization with high transmissivity is crucial for optical devices.
• Graphene-based metamaterials provide tunable electronic properties.

Purpose of the Study:

• To design and theoretically investigate a metamaterial structure for polarization rotation.
• To achieve electrical tunability of polarization rotation with high optical transmission.
• To explore the role of graphene properties and structural parameters in polarization control.

Main Methods:

• Theoretical analysis using the transfer matrix method and harmonic oscillator model.
• Numerical simulations employing the finite difference time-domain (FDTD) method.
• Modeling metamaterial layers using graphene ribbon arrays.

Main Results:

• The proposed structure achieves polarization rotation to the y-direction for arbitrary linear polarization.
• Drude absorption in graphene is identified as the mechanism for polarization rotation.
• Tunability is achieved by electrically adjusting the Fermi level and scattering rate of graphene.
• Dielectric layer thicknesses influence transmission windows for different rotation angles (90°, 45°, 135°).

Conclusions:

• The proposed graphene metamaterial structure is effective for tunable polarization rotation.
• High transmissivity is achievable through electrical tuning of graphene properties.
• Structural design, particularly dielectric layer thickness, is critical for controlling the frequency and transmission of rotated polarization.