Phys.org  November 26, 2024 A fundamental requirement for quantum technologies is the ability to coherently control the interaction between electrons and photons. However, in many scenarios involving the interaction between light and matter, the exchange of linear or angular momentum between electrons and photons is not feasible, due to the dipole approximation limit. An international team of researchers (USA – University of Maryland, Italy, Spain, Germany, Japan, Australia) conceived a mechanism for such an orbital angular momentum transfer from optical vortex beams to electronic quantum Hall states. They identified a robust contribution to the radial photocurrent, in an annular graphene […]