On-chip light trapping in bilayer moiré photonic crystal slabs

The optical response of bilayer moiré photonic structures can be precisely controlled by varying the lattice geometry. Bilayer crystal slabs exhibit flat bands in band structure, where modes have zero group velocity. They also give rise to momentum-independent light-trapping Bloch waves both transverse and vertical directions, leading high quality-factors ([Formula: see text]) small mode volumes text]). large Q V lead a Purcell enhancement text]), providing opportunities for low-threshold lasing, nonlinearities, quantum information processing.