Pattern-tunable synthetic gauge fields in topological photonic graphene

Area of Science:

• Photonics
• Condensed Matter Physics
• Materials Science

Background:

• Photonic topological insulators (PTIs) offer robust edge states for light manipulation.
• Controlling topological properties in PTIs often requires complex fabrication or external fields.

Purpose of the Study:

• To propose a straightforward and effective method for designing PTIs with high-quality edge states using strain-engineering.
• To investigate the tunability and localization of these strain-induced topological edge states.

Main Methods:

• Pattern-tunable strain-engineering to create chiral synthetic gauge fields in two domains.
• Analysis of Landau levels and topological numbers in strained photonic structures.
• Characterization of edge state properties, including quality factors, confinement, and localization.

Main Results:

• Achieved PTIs supporting high quality factor edge states through continuous strain modulation.
• Demonstrated robust time-reversal and spin-momentum-locked edge states at domain boundaries.
• Showcased remarkable field confinement and tunability, with strain controlling edge state localization.

Conclusions:

• The two-domain strain-engineering design stabilizes topological edge states.
• The approach offers large potential bandwidth and scalability for photonic applications.
• Enables applications in tunable microcavities, lasers, and quantum information processing.