Berry Monopole Scattering in the Synthetic Momentum Space of a Bilayer Photonic Crystal Slab

TL;DR

This paper demonstrates the first observation of Berry monopole scattering in a bilayer photonic crystal slab with synthetic momentum, combining theoretical modeling and full-wave simulations, and proposes an experimental approach using chiral edge states.

Contribution

It introduces the first experimental and theoretical study of Berry monopole scattering in a hybrid synthetic momentum space in photonic systems.

Findings

Monopoles approach, collide, and scatter within the hybrid parameter space.

Effective coupled-mode model accurately describes the scattering process.

Proposed experimental scheme using chiral edge states to probe monopole interactions.

Abstract

Berry monopoles-quantized sources of Berry curvature-are fundamental to topological phases, yet their scattering remains unexplored. Here, we report for the first time the adiabatic scattering of Berry monopoles in a bilayer photonic crystal slab combining one genuine and one synthetic momentum. Two monopoles approach, collide, and scatter within this hybrid parameter space. The process is described by an effective coupled-mode model and confirmed by full-wave simulations. We further propose an experimental scheme using chiral edge states, opening a route to probe monopole interactions in synthetic photonic systems.