High-Resolution Wavefront Microscopy for Applications in Bio-Imaging, Nanophotonics and Micro-Scale Thermometry

Dr. Guillaume Baffou, CNRS researcher at Institut Fresnel, Marseille (France)

Presented in-person in Goergen 101 and on Zoom

Zoom Information

Zoom:https://rochester.zoom.us/j/91669460596?pwd=T1VzbEFreVd3NFR5QnlUV09YWlZWZz09
Meeting ID: 916 6946 0596
Passcode: 0330

Abstract

Cross-grating wavefront microscopy (CGM) is an optical technique capable of mapping the wavefront distortion of objects lying at the sample plane of a microscope, with a diffraction limited resolution. CGM is based on the use of a 2D diffraction grating placed at the vicinity of a camera sensor. In this presentation, I will introduce the CGM technique, and detail the applications we recently tackled in bio-imaging and nanophotonics. In particular, I will explain how CGM can be used as a temperature microscopy technique, in particular for applications involving laser heating of plasmonic nanoparticles. I will show how CGM can measure biomass density and single-cell growth rate in bacteria populations, and neurons in culture. I will finally explain how CGM can be used as an ideal metrology tool in nanophotonics, by measuring the complex optical polarizability of nanoparticles, the complex refractive index map of 2D materials, and the wavefront distortion of metasurfaces.

Biography

Guillaume Baffou is a CNRS researcher working at the Institut Fresnel, Marseille (France). He is a graduate of the École Normale Supérieure de Cachan (ENS Cachan, recently renamed ENS Paris-Saclay). He passed the 'agrégation' in physics in 2003 and received his master's degree in solid states physics in 2004, from Université Paris XI. After a Ph.D. degree in Nanoscience at the Université Paris XI in 2007, he moved to the ICFO, Castelldefels (Barcelona) for a 3-year-long postdoc on plasmonics and associated photothermal effects, under the supervision of Prof. Romain Quidant. In 2010, he was appointed CNRS researcher at the Institut Fresnel, Marseille (France) in the Mosaic group.

Guillaume Baffou was awarded the Bronze Medal of the CNRS in 2015. In 2018, he obtained an ERC Consolidator grant to lead research activities at the interface between physics and biology at small scales. In 2023, he was awarded a Fulbright grant to work in the biological sciences department at Columbia University, NY, for a year.