Controllable orbital–angular–momentum Hall effect by engineering intrinsic orbit–orbit interaction

Abstract

We report both theoretically and experimentally a process of optical intrinsic orbit–orbit interaction with a vortex–antivortex structure nested in a freely propagating light field. The orbit–orbit interaction is originating from the coupling between different vortices and antivortices. Based on this process, we reveal the resultant controllable orbital–angular–momentum Hall effect by considering a typical structure, which comprises a vortex–antivortex pair and another vortex (or antivortex) as a controllable knob. The intrinsic Hall effect can be spatially manipulated by appropriately engineering the orbit–orbit interaction, namely arranging the initial distribution of these elements. This work can find interesting potential applications. For example, it provides an effective technique for controllable paired photon generation.