Configurable phonon polaritons in twisted α-MoO3.

Moire engineering is being intensively investigated as a method to tune the electronic, magnetic and optical properties of twisted van der Waals materials. Advances in moire engineering stem from the formation of peculiar moire superlattices at small, specific twist angles. Here we report configurable nanoscale light–matter waves—phonon polaritons—by twisting stacked α-phase molybdenum trioxide (α-MoO3) slabs over a broad range of twist angles...