Curriculum vitæ

French

Prof. Jean-Christophe VALMALETTE Institut Matériaux Microélectronique et Nanosciences de Provence (IM2NP) CNRS UMR 6242 Université du Sud Toulon et du Var BP 20132 F-83957 La Garde Cedex valmalette AT univ-tlv.fr +33.494.14.24.76

Publications

Since 2004, Jean-Christophe Valmalette has been Professor in Physics, Université du Sud Toulon Var (France), Institut Matériaux Microelectronique et Nanosciences de Provence (IM2NP UMR 6242 CNRS), Department of Materials and Nanoscience.

Following a first academic training in physical chemistry, he passed his Master's Degree in Materials Science in 1991 at Bordeaux University (France). Also in 1991, in St-Petersburg University (Russia), he got to work on one of the very first Scanning Probe Microscopes (SPM) for characterizing Si/WO₃ structures. He got his PhD in Materials Science in 1994 at Toulon University (France). His thesis work was dedicated to “Synthesis and Switching Optical Properties of Vanadium Dioxide Nanoparticles”. This work also led to apply for a patent (PCT/FR95/01450). He also conducted structural investigations on the metastable VO₂(B) phase by XRD, TEM and vibrational spectroscopy. .

From 1995 to 1997, he occupied a post-doctoral position at the Swiss Federal Institute of Technology of Lausanne (Switzerland). He was responsible for a project dealing with plasmonics applied to the coloration of 3Y-TZP ceramics in collaboration with Asulab S.A. He developed the Effective Medium Theories on model systems such as Au/Ag Nanorods obtained by template process, in collaboration with C.R. Martin from Colorado State University. During this time, he also studied the optical properties of gold NP obtained by the “inversed micelles” method in collaboration with J. Hilborn (Polymer Laboratory, EPFL)

In 1997, Prof. J. C. Valmalette was appointed Assistant Professor at University of Toulon (France). His research leads him to enrich his expertise with vanadium dioxide, which gave him the opportunity to work within the framework of a contract with DGA (Ministry of Defense) on thermochromic materials. He pointed to the relationship between IR emissivity contrast, cationic substitution (W, Nb, …) of vanadium, and VO₂ semiconductor-metal transition. At the same time, he conducted a work on percolating properties of insulator/metal granular media for sensors applications in collaboration with Made Society (France), and on ionic conductivity of LiVO₃ by X-Rays and Neutrons diffractions.

In 2002, Prof. J. C. Valmalette published new initial results on the reactive nanostructuration of Zr_xAu_y and Ce_xAu_y intermetallic compounds leading to the formation of Au-ZrO₂ and Au-CeO₂ nanoparticles at room temperature. He used synchrotron radiation, neutron diffraction and Raman spectroscopy to explain this unexpected mechanism leading for the first time to the formation of 3 nm monoclinic ZrO₂ crystals. He suggested at thermodynamical model for interpreting the size-effect on the structural transition (m)«(t). New catalytic properties are now obtained from these nanostructured materials.

Since 2003, Prof. J. C. Valmalette has been working on the mechanism of self-assembled nano-crystals of CuC₂O₄, leading to 2D and 3D mesocrystals. The architecture of these assemblies strongly depends on crystallographic features and the use of polymeric additives during synthesis. He was involved in several projects including STREP (EU Programs) in relation with the downscaling in microelectronics.

Starting in 2005, he coordinated the Nanoscale Raman Project for the IM2NP Institute in collaboration with microelectronics companies. His group is now using a Scanning Probe Microscope associated with a Raman spectrometer in a lateral configuration. This project is focused on the enhancement effects obtained by SERS substrates (applied to Self-Assembled Monolayers) and tailored probes (optical nano-antenna) obtained by bottom-up approaches. The first papers were published on the depolarizing effects induced by the AFM tips in TERS (Tip Enhanced Raman Spectroscopy) on Si(100) crystals.

He started in 2010 a collaboration with Alain Robichon (Agrobiotech - Sophia-Antipolis). He investigated a photo-induced charge transfer mechanism occurring in biological interface (published in Nature Scientific Reports) and suggested for the first time a photosynthesis-like process in insect (Nature News)

Prof. J. C. Valmalette is an expert on Raman spectroscopy, phase transitions, optical properties of materials and more generally on the relationships between structures and optical properties in solids.

Prof. J.C. Valmalette has taken responsibility for the Master of Materials Science from 2004 to 2008. He is also member of the Scientific Committee of University of Toulon (France) and involved as expert in international programs.

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