Tunable and anisotropic perfect absorber using graphene-black phosphorus nanoblock

Area of Science:

• Optics and Photonics
• Materials Science
• Nanotechnology

Background:

• Two-dimensional (2D) materials offer unique optical properties for advanced devices.
• Graphene and black phosphorus (BP) are key 2D materials with tunable electronic and optical characteristics.
• Perfect absorbers are crucial for enhancing light-matter interactions in optical systems.

Purpose of the Study:

• To numerically investigate a novel tunable and anisotropic perfect absorber.
• To explore the potential of a graphene-black phosphorus (BP) nanoblock array structure.
• To demonstrate polarization-dependent absorption in the mid-infrared spectrum.

Main Methods:

• Utilizing finite-difference time-domain (FDTD) analysis for numerical simulations.
• Designing a nanoblock array structure composed of graphene and black phosphorus.
• Investigating the effects of geometrical parameters and doping concentrations on absorption spectra.

Main Results:

• Achieved maximum absorption of 99.73% for x-polarized light and 53.47% for y-polarized light.
• Demonstrated significant polarization-dependent anisotropic absorption in the mid-infrared range.
• Showcased tunability of absorption spectra by adjusting geometrical parameters and doping levels.

Conclusions:

• The proposed graphene-BP nanoblock structure functions as an effective tunable and anisotropic perfect absorber.
• The design exhibits potential for creating polarization-selective devices in the mid-infrared.
• Results pave the way for high-performance optical and photonic devices like polarizers, modulators, and photodetectors.