Tunable optical angular selectivity in hyperbolic metamaterial via photonic topological transitions

Area of Science:

• Photonics
• Metamaterials
• Optical Engineering

Background:

• Hyperbolic metamaterials (HMMs) offer unique optical properties due to their anisotropic equi-frequency surfaces (EFS).
• Photonic topological transitions (PTTs) provide robust mechanisms for controlling light propagation.

Purpose of the Study:

• To theoretically and numerically investigate an ultra-narrow angular optical transparency window in an HMM platform.
• To explore the application of this phenomenon in super-resolution imaging.

Main Methods:

• Utilizing a low-loss HMM composed of aligned metallic nanowires in dielectric hosts.
• Tailoring the topology of the metamaterial's EFS near the PTT point.
• Investigating optical angular selectivity and tunability of the operating wavelength (λ₀).

Main Results:

• Achieved high-efficiency optical angular selectivity near normal incidence.
• Demonstrated flexible tunability of the operating wavelength (λ₀) via material and geometrical parameters.
• Showcased super-resolution imaging capabilities with a resolution of at least λ₀/4 over distances greater than 12λ₀.

Conclusions:

• The designed HMM system effectively creates an ultra-narrow angular optical transparency window.
• The tunable nature and super-resolution imaging potential highlight promising applications in light manipulation and lensless on-chip imaging.