recent research work
Recently released in Optics Letters, our article reports on the use of a commercial wavefront sensor to directly monitor and image the Gouy phase shift in photonic nanojets created by micrometer-sized dielectric spheres.
Compared to previous demonstrations, our approach does not require interferometric heterodyne or homodyne detections. Just plug-in the Sid4Bio camera from Phasics on the left/right port of the microscope, run the software, and get the phase image.
Such direct phase imaging using a commercial wavefront sensor should find applications in microscopy, diffractive optics, optical trapping, and point spread function engineering.
Metal subwavelength apertures have turned into essential devices to manipulate light at the nanoscale. However, experimentally characterizing the amplification brought by the nanoaperture on the excitation intensity remains a scientific and technical challenge. Such characterization is highly needed to fully understand and optimize the aperture’s design.
Our recent Optics Express manuscript describes a novel experimental method to directly characterize the aperture amplification on the excitation field independently on the emission process. We take advantage of the intrinsic nonlinear dependence of the fluorescence signal on the excitation intensity.
The most funny part is that we report enhanced nonlinear light-matter interaction using only a HeNe laser with less than 1mW CW power.
Recently released in International Journal of Optics, this study describes how to show enlarged values of fluorescence enhancement factor using optical (plasmonic) antennas without changing the antenna design. The discussion here focuses on the influence of excitation intensity, reference quantum yield and collection efficiency. Some general formulas are given, which should help avoid some confusions.
To my knowledge, this is also the first reference of Didier Wampas in a research article. Enjoy!
One of the ultimate challenges in biology is to understand the relationship between the structure, function and dynamics of biomolecules in their natural environment: the living cell. The goal of NANO-VISTA is to exploit novel concepts of photonic antennas to develop a new generation of bionanophotonic tools for ultrasensitive detection, nanoimaging and nanospectroscopy of biomolecules, both in-vitro and in living cells.The NANO-VISTA project, started on November 2011 is funded by the European Commission’s 7th research Framework programme. See the official NanoVista website.