Progress in quantum structured light

Davıd L. Andrews

Mwezi Koni, Shawal Kassim, Paola Concha Obando +3 more

Robert Fickler, Rafael F. Barros, Andre L. S. Santos Junior +1 more

Xu-Li Yan, Rui-Ping Jia, Zhou-Xiang Wang +2 more

The high-precision estimation of spatial parameters, such as transverse displacement, beam tilt and angular rotation, is of great importance in precision measurement, optical imaging and quantum sensing. Structured light, with controllable spatial modes and special momentum degrees of freedom, provides new opportunities to promote the encoding and readout of quantum metrology for spatial parameters. Here, we review recent progress in structured-light-enabled quantum metrology for spatial parameter estimation. The theoretical foundations of parameter estimation are introduced, based on which the modal-encoding mechanisms of higher-order structured light modes in spatial parameter measurements are summarized. Representative studies in which structured light is combined with nonclassical resources and the mode-matched readout strategies to achieve quantum enhancement are also demonstrated. In addition, current technical bottlenecks and future directions are discussed.

Ramarao Inguva

Andrew Forbes

Quantum structured light offers a roadmap to high-dimensional and multi-dimensional quantum states by exploiting all of light’s many degrees of freedom at the quantum level. In this talk, I will review the recent progress in quantum entanglement of photons in their spatial degree of freedom: quantum structured light. I will explain how to create high-dimensional quantum states in the laboratory, how to measure them, and review the present state of the art in the field. I will show how the patterns can be abstracted, mixing degrees of freedom to produce quantum topologies in light, introducing new paradigms for quantum state observables and classification. Finally, I will outline the advantages and disadvantages of using such single photon and entangled states in real-world applications, offering a perspective on the present challenges and exciting opportunities in the field.