Twisted light gives electrons a spinning kick: Researchers develop a novel way to control quantum interactions

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 […]

A simple way of sculpting matter into complex shapes

Science Daily  August 12, 2022 Researchers in the UK modeled propagation of far-red-detuned optical vortex beams through a Bose-Einstein condensate using nonlinear Schrödinger and Gross-Pitaevskii equations. They showed the formation of coupled light-atomic solitons that rotate azimuthally before moving off tangentially, carrying angular momentum. The number, and velocity, of solitons, depends on the orbital angular momentum of the optical field. Using a Bessel-Gauss beam increases radial confinement so that solitons can rotate with fixed azimuthal velocity. According to the researchers the model provides a highly controllable method of channeling a BEC and atomic transport…read more. TECHNICAL ARTICLE 

New devices produce and detect twisted light

Physics World  May 19, 2020 Development of a dynamically tunable OAM light source is a critical step in the realization of OAM modulation and multiplexing. An international team of researchers (USA – University of Pennsylvania, Northeastern University, Italy, Spain) harnessed the properties of total momentum conservation, spin-orbit interaction, and optical non-Hermitian symmetry breaking, demonstrated an OAM-tunable vortex microlaser, providing chiral light states of variable topological charges at a single telecommunication wavelength. The scheme can be further scaled up for simultaneous multivortex emissions in a flexible manner. The work provides a route for the development of the next generation of multidimensional […]