Hole-based stealthy hyperuniform semiconductor computational metamaterials for the mid-infrared.

Area of Science:

• Metamaterials and Nanophotonics
• Solid-State Physics
• Optical Engineering

Background:

• Photonic crystals offer unique optical properties but suffer from spatial anisotropy, limiting their use in applications requiring angle-independent performance.
• Stealthy-hyperuniform heterostructures present an alternative with analogous properties to photonic crystals but without inherent spatial anisotropy.
• Metamaterials are engineered materials with properties not found in naturally occurring substances, enabling novel functionalities.

Purpose of the Study:

• To design, fabricate, and characterize a novel hole-based stealthy-hyperuniform structure.
• To investigate the optical properties of this structure, particularly its photonic band gap and angular response.
• To evaluate the potential of stealthy-hyperuniform heterostructures for optical image processing applications away from normal incidence.

Main Methods:

• Fabrication of a hole-based stealthy-hyperuniform structure on a quantum cascade layer substrate.
• Characterization using infrared spectral analysis.
• Measurement of reflection spectra at varying incidence angles and in-plane rotational angles.

Main Results:

• A significant photonic band gap was observed around 12.0 μm, characterized by an enhanced reflection region.
• A substantial gap-midgap ratio of 10.4% was achieved, indicating a robust band gap.
• The structure exhibited spatial isotropy, with reflection spectra remaining unchanged for all in-plane rotational angles, even at increasing incidence angles.

Conclusions:

• The designed stealthy-hyperuniform heterostructure demonstrates a wide photonic band gap suitable for optical applications.
• The observed spatial isotropy confirms the advantage over traditional photonic crystals for angle-independent performance.
• These findings highlight the potential of stealthy-hyperuniform metamaterials for advanced optical image processing and other photonic devices.