Design of a dynamic multi-topological charge graphene orbital angular momentum metalens

Traditional OAM generation devices are bulky and can generally only create OAM with one specific topological charge. Although metasurface-based devices have overcome the volume limitations, no tunable metasurface-based OAM generators have been demonstrated to date. Here, a dynamically tunable multi-topological charge OAM generator based on an ultrathin integrable graphene metalens is demonstrated by simulation using the detour phase technique and spatial multiplexing. Different topological charges can be designed on different focal planes. Stretching the OAM graphene metalens allows the focal plane and the topological values to be changed dynamically. This design method paves an innovative route toward miniaturization and integrating OAM beam-type photonic devices for practical applications.

Automated summary

Traditional OAM generation devices are bulky and limited to creating OAM with one specific topological charge. This study demonstrates a tunable multi-topological charge OAM generator based on an ultrathin integrable graphene metalens. Different topological charges can be designed on different focal planes and dynamically changed by stretching the graphene metalens. This design method paves the way for miniaturization and integration of OAM beam-type photonic devices.