Anisotropic moire optical transitions in twisted monolayer/bilayer phosphorene heterostructures

Moire superlattices of van der Waals heterostructures provide a powerful way to engineer electronic structures of two-dimensional materials. Many novel quantum phenomena have emerged in graphene and transition metal dichalcogenide moire systems. Twisted phosphorene offers another attractive system to explore moire physics because phosphorene features an anisotropic rectangular lattice, different from isotropic hexagonal lattices previously reported. Here we report emerging anisotropic moire optical transitions in twisted monolayer/bilayer phosphorenes. The optical resonances in phosphorene moire superlattice depend sensitively on twist angle and are completely different from those in the constitute monolayer and bilayer phosphorene even for a twist angle as large as 19 degrees. Our calculations reveal that the Gamma -point direct bandgap and the rectangular lattice of phosphorene give rise to the remarkably strong moire physics in large-twist-angle phosphorene heterostructures. This work highlights fresh opportunities to explore moire physics in phosphorene and other van der Waals heterostructures with different lattice configurations. Twisted phosphorene offers another attractive system to explore moire physics. Here, the authors report emerging anisotropic moire optical resonances in twisted monolayer/bilayer phosphorene, exhibiting strong twist dependence for angles as large as 19 degrees.

Automated summary

The researchers observed emerging anisotropic moire optical transitions in twisted monolayer/bilayer phosphorene, showing strong twist dependence even for angles as large as 19 degrees.