One week ago, Kuidong Wang went back to China after 4 years spent in the lab, as a postdoctoral researcher. He now got an associate professor position in Xi’an. We really appreciated his presence among us and his investment in the research project he took part to.
We wish him all the best for the future !
We welcome since the 1st of July Rahul Meena, phD in Université Libre de Bruxelles under the supervision of Pr. Yves Geerts, in the context of the UHMob program. Rahul comes from Rajasthan in India and received his master degree from IISER Bhopal. He is currently working on synthesizing new organic semiconductors having high carrier mobility, that will be tested under strong coupling with conductivity measurements. He will stay 2 months in the lab, in office n°106.
Kalaivanan Nagarajan left our lab one week ago to go back in India where he will take a position of reader at the Department of Chemical Sciences of TIFR, Mumbai. He spent 5 years in the lab, during which he had time to build strong relationships with people here, to evolve as a scientist with a pure chemistry education to a much more physics one and to forge a family. His presence in the team was precious thanks to his energy and enthusiasm. No doubt that his new colleagues will benefit from this and we wish him all the best for the future !
Today, we have the pleasure to welcome Pr Hiroshi Fukumura (KU Leuven, Belgium, & Tohoku University, Japan) who will give a talk at 11am in the Salle de Conférence of ISIS, entitled
“Liquid-liquid phase separation dynamics: hierarchy from molecular level to continuous bulk”
Here below you can find the abstract of his talk :
Pulsed laser induced liquid-liquid phase separation has been studied with various time-resolved techniques. Time-resolved Raman spectroscopy and fluorescence spectroscopy revealed molecular level changes immediately after the laser pulses up to 1 . Ultrafast imaging under conventional microscopes showed macroscopic changes started 10 after the laser pulse. The macroscopic phase separation seemed to follow spinodal decomposition described by Kahn-Hilliard theory. It is, however, yet unclear what occurs in the time range between 1 and 10 . Recently we have succeeded in observing this time range with time-resolved structured illumination as well as optical diffraction techniques. Possible explanation of our results would be that mesoscopic entities like micelle-like structures mediate between molecular level changes and macroscopic spinodal decomposition. Related topics like liquid-liquid phase separation in living cells, critical Casimir force in binary liquids, laser ablation and implantation of polymer surfaces may be introduced.
On wednesday, 1st of June, during the ITI QMat scientific day held at IPCMS, Rémi Goerlich won the 1st prize for his poster “Harvesting information to control non-equilibrium states of active matter”.
Congratulations to him !
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.
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 !
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.
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.
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 light−chiral 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.
