(Not quite) newcomer !

With a bit of delay, we introduce you to our new Master 2 student, Antoine Tartar. He started his training in the lab in the beginning of February and he is currently working on setting up a new optical trap under vacuum with Rémi Goerlich and Luis Pires, under the supervision of Cyriaque Genet.

2022 Mozi Award for Thomas Ebbesen

The conference SPIE Photonics Europe started yesterday in Strasbourg and on this occasion Thomas Ebbesen received this morning the 2022 Mozi award.  This award was established by the Taiwan Information Storage Association (TISA) and SPIE in 2017. It is named in honor of the Chinese philosopher, scientist, and engineer, Mozi (468-391 BC), the first person in recorded history to mention the simple principles behind the concept of camera obscura. Congratulations !

Seeds of 2D chirality grow 3D…

In a new publication in ACS Photonics, we show that optical spin orientations can be locked to intracavity propagation directions when a seed of planar (2D) chirality is present inside the cavity. This seed is given by inserting between the two metallic mirrors of a Fabry–Perot cavity a layer of polystyrene made 2D chiral under torsional shear stress. This planar chirality gives rise to an extrinsic source of three-dimensional chirality under oblique illumination that endows the cavities with enantiomorphic signatures measured experimentally and simulated with excellent agreement. The simplicity of this scheme is particularly promising in the context of chiral cavity QED and polaritonic asymmetric chemistry, driven by chiral polaritonic states.

A nano letter but a large optical non linearity !

Another paper, resulting from the collaboration between our group and Institute of Electro-Optical Engineering from National Taiwan Normal University, has been published in Nano Letters. Strong coupling provides a powerful way to modify the nonlinear optical properties of materials but the coupling strength is restricted by a weak-field confinement in cavities, which limits the enhancement of the optical nonlinearity. Here, we investigate a strong coupling between Mie resonant modes of high-index dielectric nanocavities and an epsilon-near-zero mode of an ultrathin indium tin oxide film and obtain an anticrossing splitting of 220 meV. In addition, static nonlinear optical measurements reveal a large enhancement in the intensity-independent effective optical nonlinear coefficients, reaching more than 3 orders of magnitude at the coupled resonance.

New publications

Just before he went back to India, the paper written by Sandeep Kulangara as first author has been accepted in Journal of Physical Chemistry Letters. The effects of cooperative vibrational strong coupling on the aggregation of two structural isomers of phenyleneethynylene was investigated and showed to lead to two different self-assembled structures, spheres and flakes, having distinct optical properties. These results confirm that VSC can be used to drive molecular assemblies and thereby provide a new tool for supramolecular chemistry.

In addition, Cyriaque Genet just published a perspective on chiral light and chiral matter interactions in ACS Photonics. In this paper, he shows how chiral optical forces shed new light on chiral lightchiral matter interactions. The key advances selected are representative of the vitality of the current research activity and clearly point toward future designs for all-optical chiral separation strategies of high potential.

വിട സന്ദീപ് ! (*Vita Sandeep !)

Our colleague Sandeep Kulangara, who was here for a postdoctoral position for 2 years, left us one week ago to go back in India. We greatly appreciated his discreet and efficient presence in the team. He started again in his former position of assistant professor at Government Victoria College Palakkad.
Good luck to him !

Welcome to Lucia !

Lucia Di Virgilio joined us last week and will stay in our lab for two months. She is a phD student at MPI Mainz, under the supervision of Pr Misha Bonn and part of the UHMob program. Lucia is originated from Basilicata region in Italy and did her master on cold atoms in Pisa, where she first discovered physics in cavities. Now she studies the transport properties of conductive molecular materials under strong coupling regime, thanks to Thz spectroscopy. If you want to meet her, she will be staying in room 106 of our lab. Welcome to her !


Gian Lorenzo’s departure

Gian-Lorenzo Paravicini-Bagliani, who was working with us as a postdoctoral researcher since two years, left the lab in December. He found a position in Zürich, in the research and development department of Sensirion, which is a young company developing and producing a range of innovative digital environmental sensors for different industries. We wish him good luck in this new job !



Our best wishes for the new year to our friends, our present and past collaborators around the world and to the visitors of this website ! Let’s hope 2022 will be as peaceful and beautiful as this alsatian landscape under the sunset.

Chiral objects in chiral environments

The left-handed versus right-handed asymmetry of our living world—a “chirality” seen most often in mirror-image architectures of many biomolecules—is one of its most striking features yet one of the most difficult to comprehend. Immersing chiral molecules within chiral environments is an important route to asymmetry, exploited in chemistry for synthesizing and separating chiral molecules according to their handedness. However, the thermodynamics of such a route is not well understood. In a new publication in Physical Review X, we theoretically explore this thermodynamics using a chiral nanoparticle diffusing within a chiral optical light field.

Demonstrating how chiral degrees of freedom can turn into genuine thermodynamics parameters yields a new and rich playground for further exploring chiral light-matter interactions with far-reaching consequences. To that end, we build a stochastic optomechanical model to reveal and control the mechanisms of asymmetry. One central result of our work is to highlight the thermodynamical significance of the coupling between the chirality of the particle and the chirality of the light field.

Our results pave the way to new opportunities in the context of chiral sensing, recognition, and separation of chiral objects at the nanoscale that should now be implemented experimentally and exploited.