Twenty-five years ago Allen, Beijersbergen, Spreeuw, and Woerdman published their
seminal paper establishing that light beams with helical phase-fronts carried an orbital …

Structured light is derived from the ability to tailor light, usually referring to the spatial control
of its amplitude, phase, and polarization. Although a venerable topic that dates back to the …

As they travel through space, some light beams rotate. Such light beams have angular
momentum. There are two particularly important ways in which a light beam can rotate: if …

Quantum entanglement, plays a vital role in many quantum-information and communication
tasks. Entangled states of higher-dimensional systems are of great interest owing to the …

Structured light has become topical of late, where controlling light in all its degrees of
freedom has offered novel states of light long predicted, enhanced functionality in …

Entanglement of the properties of two separated particles constitutes a fundamental
signature of quantum mechanics and is a key resource for quantum information science. We …

Quantum mechanics is now a mature topic dating back more than a century. During its
scientific development, it fostered many technological advances that now are integrated into …

Entangled photon pairs are a critical resource in quantum communication protocols ranging
from quantum key distribution to teleportation. The current workhorse technique for …

Quantum metrology bears a great promise in enhancing measurement precision, but is
unlikely to become practical in the near future. Its concepts can nevertheless inspire …

The transverse spatial effects observed in photon pairs produced by parametric down-
conversion provide a robust and fertile testing ground for studies of quantum mechanics …