Structured light : physical and geometrical properties

Principal investigator : Miguel A. Alonso

Keywords : structured light, propagation-invariant beams, birefringence, geometric phase, nonparaxial light, spin-orbit interaction, Mie scattering.

This work involves the study of optical fields whose spatial and/or temporal structure in amplitude, phase and/or polarization is tailored to present a specific set of properties. One such class of fields are the “propagation-invariant beams”, whose intensity profile is preserved under propagation up to a rigid transformation. These beams have been used in applications such as imaging with enhanced depth of focus, light-sheet microscopy, optical trapping, and nanofabrication. However, they are also interesting from a geometrical/mathematical point of view, and they often provide interesting analogies with phenomena in other areas of physics. In particular, the use of the ray model reveals otherwise hidden geometric constraints that rule the spatial structure of these beams.

Other areas of study include : paraxial and nonparaxial fields with interesting polarization distributions, as well as birefringent optical elements that can be used to generate these fields ; the theoretical description of such birefringence elements and the concept of geometric phase ; the interaction of polarization with intensity and orbital angular momentum for nonparaxial fields (spin-orbit interaction) ; nonparaxial closed-form solutions to Maxwell’s equations and their use to study the interaction of focused fields with spherical scatterers.

Publications

2023

2022

2021

2020