Plasmonic Absorption Enhancement in Elliptical Graphene Arrays

Area of Science:

• Optics and Photonics
• Materials Science

Background:

• Graphene's unique electronic properties make it suitable for optical applications.
• Tunable absorbers are crucial for advanced optical devices.

Purpose of the Study:

• To design and simulate a wavelength-tunable absorber based on elliptical graphene arrays.
• To investigate methods for enhancing light absorption in the far-infrared and terahertz regions.

Main Methods:

• Numerical simulations were employed to analyze the optical properties of the proposed structure.
• The effects of geometric parameters (ellipse axis length) and material properties (graphene chemical potential) on absorption were studied.
• TM- and TE-polarization incidence angles were varied to optimize absorption.

Main Results:

• Absorption enhancement was achieved by increasing the ellipse's long axis, optimizing incidence angles for TM- and TE-polarization, and increasing graphene's chemical potential.
• The original elliptical graphene array structure exhibited higher absorption compared to its complementary structure.
• The absorption rate of a double-layer structure was studied in relation to SiO₂ thickness.

Conclusions:

• The proposed elliptical graphene array absorber demonstrates tunable absorption in the far-infrared and terahertz spectra.
• The findings suggest potential applications in tunable spectral detectors, filters, and sensors.