Information-entropy enabled identifying topological photonic phase in real space

Area of Science:

• Physics
• Information Theory
• Materials Science

Background:

• Topological photonics is crucial for fundamental physics and photonic devices.
• Traditional momentum-space design methods for topological systems are indirect and inconvenient, especially for perturbed or coupled systems.

Purpose of the Study:

• To propose an interdisciplinary approach for studying topological systems in real space.
• To combine information entropy with topological photonics for a more direct analysis.
• To develop a convenient method for identifying topological phases in complex photonic systems.

Main Methods:

• Utilizing information entropy as a tool to analyze topological properties in real space.
• Applying the method to the Kagome model as a proof of concept.
• Validating the approach with the Su-Schrieffer-Heeger model and valley-Hall photonic crystals.

Main Results:

• Demonstrated that bandgap closing does not necessarily lead to the disappearance of topological edge states.
• Showcased the ability of information entropy to conveniently and directly identify topological phases.
• Confirmed the method's effectiveness even in the presence of perturbations or couplings.

Conclusions:

• Information entropy provides a direct and convenient method for studying topological photonic phases in real space.
• This interdisciplinary approach offers new insights into analyzing physical properties by integrating information theory.
• The method is applicable to various topological photonic systems, including those with perturbations and couplings.