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 (...)

Quadriwave lateral shearing interferometry appears as a powerful tool for metrology in Nanophotonics, for characterization of nanoparticles, 2D-materials and metasurfaces.

Studying the organisation of living matter
Principal investigator : Loïc Le Goff, Manos Mavrakis
keywords : cytoskeletal filaments, Drosophila, cell division, morphogenesis, tissue growth, mechanics
More on Manos Mavrakis’ research More on Loïc Le Goff’s research
We are interested in how animal cells and tissues generate, maintain and adapt their shape as they grow, divide and reorganize during physiological responses. Our work aims at providing insights into (1) the interplay (...)

Principal investigator : Miguel A. Alonso
Keywords : polarization, SEO, q-plate, shearing interferometry, birefringence, scatterometry.
This work involves the measurement of nanostructures by using light with tailored polarization distributions, the measurement of the phase of light by using polarization-modifying optical elements, and the measurement of the polarization of light. These measurements are based on the use of spatially-varying birefringent optical elements such as (...)

Principal investigator : Miguel A. Alonso
Keywords : imaging ; optical performance, mid-spatial frequency error, Strehl ratio, OTF, PDPD, ray-based methods, Wigner function.
The performance of imaging systems is hindered by manufacturing errors in the optical elements involved. These errors can be the standard aberrations, but also finer-scale imperfections known as mid-spatial frequency errors, resulting from the manufacturing/finishing process, particularly if sub-aperture tools are (...)

Principal investigator : Miguel A. Alonso
Keywords : partial coherence, polarization, Wigner function, Ambiguity function, entanglement.
This work includes theoretical and experimental studies of correlations between optical fields at different points (spatial coherence), at different times (temporal coherence), or for different field components (polarization). At the theoretical level, different formalisms are proposed for modeling partially coherent light, including phase space (...)

Principal investigator : Thomas Chaigne
There is currently no technique to image neuronal activity with cellular resolution (∼ 10 µm), with large fields of view (∼ 1 cm ) deep inside the brain (> 1 mm), while resolving single action potentials (∼ 1 ms). Most efforts are devoted to scaling up multi-photon fluorescence microscopy to image increasingly larger and deeper populations of neurons, but these techniques are inherently limited by light scattering to shallow depths. So we add (...)

One-step homogeneous detection assay with dual color light scattering on nanoparticles
Principal investigator : Jerome Wenger, Stéphanie Vial
We introduce a novel technique for high sensitivity specific molecular biosensing in a single step homogeneous solution phase. Our approach is based on dual-color illumination and detection of the scattering intensities from silver and gold nanoparticles. In the absence of the target molecule, the silver and gold nanoparticles move independently (...)

Single molecule fluctuation dynamics reveal protein size, structure and affinities
Principal investigator : Jerome Wenger
Fluorescence Correlation Spectroscopy uses a confocal microscope to collect the light from luminescent molecules moving across a femtoliter observation volume (one femtoliter volume is one micron cube). The fluctuating number of fluorophores in this observation volume gives rise to intensity fluctuations which provide information about diffusion, molecular (...)

using gold nanoparticles as nanosources of heat
Principal investigator : Guillaume Baffou
keywords : nanoplasmonics, gold nanoparticles, thermal effects, optical and thermal imaging
Our research activities stand at the frontiers between nanooptics and thermodynamics. We investigate thermal-induced processes at the nano and micro scales using photothermally excited gold nanoparticles [13].
I - Experimentally
Our major contribution to this field of research (named thermoplasmonics) (...)