"Deflection of electromagnetic waves by pseudogravity in distorted photonic crystals" (2023) https://journals.aps.org/pra/abstract/10.1103/PhysRevA.108.0... :
> We demonstrate electromagnetic waves following a gravitational field using a photonic crystal. We introduce spatially distorted photonic crystals (DPCs) capable of deflecting light waves owing to their pseudogravity caused by lattice distortion