Magnetically tunable singularity of Moire bound states in the continuum

TL;DR

This paper explores how applying magnetic fields can control topological singularities in magneto-optical Moiré bound states in the continuum, revealing tunable high-Q resonances for advanced photonic applications.

Contribution

It demonstrates magnetic field manipulation of topological singularities in Moiré BICs, a novel approach for dynamic control of optical resonances.

Findings

Magnetic fields can effectively manipulate the topological singularities of Moiré BICs.

Breaking time-reversal symmetry enhances the control over the high-Q resonances.

Moiré BICs exhibit robust topological features across momentum space.

Abstract

We investigate the band structure and the dynamics of topological singularities of magneto-optical Moir\'e bound states in the continuum (BICs), which originate from two overlapped conventional magneto-optical BIC gratings with mismatched periods. We show that breaking time-reversal symmetry by applying an external magnetic field in different directions can effectively manipulate the Moir\'e BICs' topological singularities, which exhibit a high Q factor throughout the momentum space.