recent research work

Published recently in Optics Express, it’s freely available at :
http://www.opticsinfobase.org/abstract.cfm?URI=oe-16-10-6930

We investigate the focusing of light by single latex microspheres illuminated by a collimated beam. Measurements are performed with a fast scanning confocal microscope in detection mode, where the detection pinhole defines a diffraction-limited observation volume that is scanned in three dimensions over the microsphere vicinity. From the collected stack of images, we reconstruct the full 3 dimensional photonic nanojet beam created by the microsphere.

Remarkably, we measure spot sizes as small as 270 nm FWHM for a wavelength of 520 nm. The beam keeps a subwavelength FWHM over a propagation distance of more than 3 micrometers, displaying all the specificities of a photonic nanojet. 

Click on the video below to visualize the photonic nanojet :

By clicking on the “published papers” link on the left, you’ll be redirected to the ResearcherID webpage, which contains an additional link to the ResearcherID new features “Labs”. Alternatively, this can be accessed directly by http://labs.researcherid.com/mashlets/rid/?rid=A-5657-2008 

The most intriguing feature is the citing articles network, which enables you to visualize who’s citing your work. Sorting can be done by person, institutions, countries, years…

At the end, you’re on procrastinating for a few tens of minutes more, and can proudly (?) display a “citing network worldmap” as mine:

PS: my geekiness is getting worse each day…

The following meetings are scheduled :

- France/Taiwan Frontier of Science Symposium, Taiwan, June 26-27

http://www-direction.inria.fr/international/ASIE_OCEANIE/FoS_France_Taiwan/

- Gordon Research Conference on Plasmonics, Tilton NH, July 26-31

http://www.grc.org/programs.aspx?year=2008&program=plasmonics

Released in the march 03^rd issue of Optics Express : we detail the role of single nanometric apertures milled in a gold film to enhance the fluorescence emission of Alexa Fluor 647 molecules. By “detailing”, we mean we characterise the effects of the nanoaperture both on the excitation and emission phenomena that form the fluorescence process.  

The major novelty in this study is the introduction of a fluorescence characterization procedure combining fluorescence correlation spectroscopy and fluorescence lifetime measurements.

For the first time, we characterize a broad range of nanoaperture diameters from 80 to 310 nm. This allows us to highlight the link between the fluorescence enhancement and the local photonic density of states.  

These results are of great interest to increase the effectiveness of fluorescence-based single molecule detection and to understand the interaction between a quantum emitter and a nanometric metal structure.

Freely available for download :  http://www.opticsexpress.org/abstract.cfm?id=154338

Published recently in Optics Express, it’s freely available at :
http://www.opticsinfobase.org/abstract.cfm?URI=oe-16-3-2276

A single nanometric aperture surrounded by a circular channel groove in a metallic screen can increase the electric field intensity inside the central aperture up to 50 fold. Detailed analysis of cavity modes and their coupling through surface plasmon wave determine the parameters leading to maximum field enhancement. This effect can be used in high-efficiency single-molecule fluorescence analysis in attoliter volumes.