Projects
The team is organized around four research themes based on different THz spectroscopy techniques.
The team's main focus is currently on the study of topological and Dirac materials using THz and MIR magnetospectroscopy. The analysis of optical transitions between Landau levels enables us to reconstruct the band structure of these new materials (HgCdTe, InAs/GaSb, NbAs, TaAs, Cd3As2...) and to gain access to certain exotic properties of semi-relativistic fermions (Kane, Dirac, Weyl). The three experimental techniques employed are magneto-absorption, magneto-photoconductivity and Landau emission. Within the framework of this first theme, strong interactions exist with the Quantum Transport and New 2D Materials team at L2C, as well as with the NanoMIR team at IES.
La deuxième activité est liée à la biophysique et vise à expliquer les mécanismes d’interaction elecrodynamique entre les protéines au sein des cellules. Prédites dès le début du XXèmesiècle par l’électrodynamique classique et quantique, les forces intermoléculaires agissant à longue distance (<1000 angströms) n’ont jamais été démontrées expérimentalement. Dans ce cadre, l’analyse spectrale de la dynamique non-linéaire de biomolécules en milieu aqueux est réalisée par deux techniques expérimentales de spectroscopie THz en champ proche qui sont développées pour étudier les couplages internes amenant les biomolécules se synchroniser.
The team's third activity is linked to the agro-environment and is based on the analysis of the multilayer structure of plants using THz time-domain data, the spectroscopic study of intermolecular vibrations of substances contained in plants, and the development of THz tools dedicated to the response of plants to stresses (hydric, heavy metal hyperaccumulation and the circadian cycle).
The fourth research theme is the team's historical activity. It focuses on the study of collective electronic phenomena in two-dimensional electron gases. Detailed analysis of plasma waves in nanotransistors led in 2014 to a technology transfer and the creation of the Terakalis start-up, which today uses this new technology in THz imaging systems applied to industrial non-destructive testing. Today, this scientific activity naturally extends to the study of THz plasmons in new materials (such as graphene and other Dirac materials) and optoelectronic devices.