Magnetically tunable singularity of Moire bound states in the continuum

We investigate the band structure and the dynamics of topological singularities of magneto-optical Moiré 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 Moiré BICs’ topological singularities, which exhibit a high Q factor throughout the momentum space.