Topological Metamaterials.

Area of Science:

• Physics
• Materials Science
• Chemistry

Background:

• Topological properties, characterized by topological invariants, are robust global features resistant to continuous change.
• Engineered metamaterials (MMs) can exhibit non-trivial topological properties in their electronic, electromagnetic, acoustic, and mechanical responses.
• Topological concepts have emerged as a significant breakthrough in physics over the last decade.

Purpose of the Study:

• To review the foundational concepts and recent advancements in topological photonic and phononic metamaterials.
• To bridge the understanding of topological concepts across various scientific disciplines, including chemistry.
• To highlight the potential opportunities presented by topological metamaterials for chemical research and applications.

Main Methods:

• Introduction to fundamental concepts: topological charge and geometric phase.
• Discussion of topological properties in natural electronic materials.
• Review of various topological metamaterial analogues: 2D, Floquet, 3D, higher-order, non-Hermitian, and nonlinear topological MMs.

Main Results:

• Topological metamaterials demonstrate non-trivial wave interactions with broad scientific interest.
• Exploration of topological aspects in scattering anomalies, chemical reactions, and polaritons.
• Demonstration of the applicability of topological concepts beyond traditional physics domains.

Conclusions:

• Topological photonic and phononic metamaterials offer robust and tunable wave phenomena.
• These materials provide a powerful platform for exploring fundamental physics and enabling novel applications.
• The interdisciplinary nature of topological metamaterials opens new avenues for chemistry and related fields.