Polariton Z topological insulator

Area of Science:

• Condensed Matter Physics
• Photonics
• Topological Materials

Background:

• Photonic topological insulators (PTIs) are novel materials exhibiting unique edge states.
• Exciton-polaritons in microcavities offer a platform for simulating complex quantum phenomena.
• Photonic spin-orbit coupling is crucial for realizing topological phases in photonic systems.

Purpose of the Study:

• To investigate the topological properties of honeycomb arrays of microcavity pillars.
• To explore the role of photonic spin-orbit coupling and Zeeman splitting in creating topological band gaps.
• To demonstrate the formation of topologically protected edge states in this system.

Main Methods:

• Fabrication of honeycomb arrays of microcavity pillars.
• Optical spectroscopy to probe exciton-polariton properties.
• Application of external magnetic fields to induce Zeeman splitting.
• Analysis of band structure and Chern numbers.

Main Results:

• Honeycomb microcavity pillar arrays exhibit behavior of a 2D photonic topological insulator.
• The interplay of spin-orbit coupling and Zeeman splitting opens a nontrivial topological band gap.
• A unique set of band Chern numbers (C=±2) characterizes the topological gap.
• Formation of one-way, topologically protected edge states is observed.

Conclusions:

• Honeycomb microcavity pillar arrays serve as a robust platform for realizing 2D photonic topological insulators.
• External magnetic fields provide a powerful tool to control and tune topological properties in photonic systems.
• The demonstrated system opens new avenues for designing novel optical devices with topological protection.