Tunable polaritonic topologies generated by non-local photonic modes

Area of Science:

• Optics and Photonics
• Condensed Matter Physics
• Materials Science

Background:

• Photonic skyrmions offer resilience and subwavelength features for applications like microscopy and data encoding.
• Existing polaritonic skyrmion generation lacks dynamic tunability, with fixed lattice sizes and topological charges.
• Current methods rely on wavelength-dependent structures or complex excitations, limiting flexibility.

Purpose of the Study:

• To introduce dynamically controllable polaritonic topologies.
• To overcome the limitations of fixed skyrmion sizes and charges in existing methods.
• To enable versatile skyrmion generation for advanced applications.

Main Methods:

• Utilized quasi-bound states in the continuum resonances in dielectric metasurfaces.
• Launched hyperbolic phonon polaritons in hexagonal boron nitride (hBN).
• Engineered resonator shapes and controlled excitation frequency for topological control.

Main Results:

• Created highly confined photonic skyrmion lattices with diameters down to 271 nm (λ/25).
• Achieved dynamic control over individual photonic skyrmion size by changing excitation frequency in hBN.
• Generated optical meron lattices and kπ-twist skyrmions by varying resonator shape.

Conclusions:

• Demonstrated a feasible platform for dynamically controllable polaritonic topologies.
• Enabled skyrmion multiplexing and generation of near-arbitrary topologies.
• Highlighted potential applications in topological lasing, nonlinear optics, twistronics, Chern insulators, and topological edge states.