Personnel CNRS
– CNRS Senior Scientist / Groupe 1
– ORCID / Scopus profile
– Contact : prénom.nom@icmcb.cnrs.fr / poste 8811 (ligne directe 054000+poste / en interne 5+poste)
Compétences : Physics of dielectrics and ferroelectric materials / Impedance spectroscopy / Piezoelectricity
Education and scientific position
2000- : CNRS Senior Scientist Institute for Condensed Matter Chemistry of Bordeaux ICMCB – CNRS, University Bordeaux, France
1988 – 2000 : CNRS Junior Scientist Physics Laboratory / University of Burgundy / Dijon, France
2002 : Invited Professor Department of Chemistry, Tohoku University / Sendai, Japan
2006 – 2010 : Invited Professor Faculty of Sciences / University of Sfax, Tunisia
1984 – 1987 : Teaching Assistant Department of Physics/ Lausanne Federal Polytechnic School (EPFL), Switzerland
1984 – 1987 : PHD student at IBM Zürich Research Laboratory / Rueschlikon, Switzerland
Keywords
Ferroelectric and relaxor perovskites : single crystals, ceramics, composites and thin films. Dielectric ceramics and composites: contribution of conductivity to interfacial effects. Order and disorder in dielectric materials. Ionic conductivity in single crystals for Non-Linear Optics. All-dielectric meta-materials
Research activities
Summary : the disorder or the coexistence between different types of order in dielectric and ferroelectric materials have many consequences onto their macroscopic properties. Increased dielectric permittivity, frequency dispersion, agility under external stresses, unrivalled piezoelectricity, multiferroism are all properties I have investigated and still am interested in. Another coexistence of deep impact is the insertion of free electronic or ionic charges in dielectrics; their localisation at all types of interfaces can increase the dielectric properties towards exceptional and artificial values. (The references in the text below refer to the publication list at the bottom)
Order and disorder in ferroelectric perovskites
Among the materials flexibilities, maximal piezoelectricity is very specific to ferroelectric perovkites. In the solid solution BaTiO3-CaTiO3-BaZrO3 (BCTZ), using high-resolution X-ray diffraction at ESRF synchrotron, we were able to show that the most interesting piezoelectric coefficients are obtained when achieving a convergence between the 4 phases of perovskites: cubic, tetragonal, orthorhombic, rhomboedral. Intermixing of different phases is thus needed for large piezoelectricity in BCTZ. (ref 4). We confirmed that such link is operative in powders, ceramics, single crystals and thin films for the same composition range. This demonstrates the intrinsic nature of this link. Scanning the full compositional diagram of this complex solid solution was achieved spontaneously during the growth of large size single crystals including composition gradient. A systematic scanning was also achieved in thin films using combinatorial PLD and robotized measurements of the dielectric parameters (ref 5)
Charged interfaces in dielectrics
Introducing charged defects in dielectric oxides may lead to extremely large increase of the dielectric permittivity. We have shown that such an extrinsic effect results from free charges accumulation either at single crystals surfaces (ref 6) or at grain boundaries in ceramics (ref 7). An example is given on the figure (ref 6) where the dielectric permittivity of BaTiO3 crystals undergoes a large maximum at high temperatures whose amplitude largely depends on the crystals oxidation state. This was ascribed to electronic space charges originating from oxygen vacancies, which are donor centres. Note that the ferroelectric transition temperature at 130°C is insensitive to the reduction state. In ceramics, the fast sintering processes like Spark Plasma Sintering are helpful to quench highly reduced states thus increasing the Free ions may as well accumulate close to the surface of single crystals as shown in KTiOPO4 single crystals used for Second Harmonic Generation in solid-state lasers (ref 10).
Past and active collaboration having led to a joint publication:
-IBM Zürich Research – Zürich – Switzerland – (U.T.Höchli, K.A. Müller)
-Mainz University – Germany (A.Loidl, K.Knorr)
-Pavia University – Italy (G.Lanzi, F.Borsa)
-Swiss Polytechnic School of Lausanne -Switzerland (J.V.D.Klink,)
-Porto University- Portugal – ( M.R.Chaves)
-Louvain La Neuve University – Belgium (J.P.Michenaud, L.Piraux)
-Metz University – France (M.Fontana)
-Paris VI University – France (M.Fischer)
-Department of Material Science -University of Urbana and NSL Brookhaven-USA (H.Chen)
-Institute of Physics -Univ. Katowice -Poland (K.Roleder, H.Handerek)
-Center for High Temperature Physics of Orléans CNRS– France (P.Simon)
-Dijon University Hospital and School of Food Sciences of Dijon – F (E.Giroux, M.Le Meste)
-INSA Lyon – France (G.Fantozzi, M.Gabay, L.David)
-Dijon University – France (J.C.Niepce, S.Bourgeois)
-Rennes University – France (S.Beaufils)
-Thales Central Laboratory – France (J.P.Ganne, M.Paté, M. Pham Thi)
-National Polytechnic Institute of Grenoble -France ( J.Kreisel, C. Dubourdieu)
-Ukrainian Academy of Sciences Kiev – Ukraine (M.Glinchuk)
-Sfax University – Tunisia (H.Khemakhem)
-Materials Research Centre Bangalore – India (K.B.R.Varma, A.Umarji)
-Vancouver University – Canada (Z.G.Ye)
-Toulouse University – France (C.Estournes, R.Plana)
-Aveiro University – Portugal (A.Kholkin)
-Nanyang Technological University Singapore (W.Zhu)
-Caen University – France (W.Prellier)
-Russian Academy of Sciences L.V.Kirensky Institute Krasnoiarsk – Russia (I.Flerov)
-Technological University Darmstadt – Germany (H.Fuess, A.Klein, J.Roedel)
-Oregon State University Corvallis – USA (M.Subramanian)
-Max Planck Institute Stuttgart – Germany (A.Bussman Holder)
-Max Planck Institute Halle –Germany (I.Vrejoiu)
-National Institute for Materials Sciences, NIMS Tsukuba- Japan (K.Shimamura)
-STMicroelectronics Tours – France (G.Guegan, E.Bouyssou, P.Poveda)
-Orléans University – France (J.Wolfman)
-Institut Lippmann Luxemburg (J.Kreisel)
Experience in European and international projects:
-Workpackage Leader “New architecture for passive microelectronics” in the FAME European Network of Excellence (FP6) (2004-2008)
-Local leader of the MACOMUFI STREP (2006-2010)
-Leader of the Marie Curie action EPREXINA (2010-2013)
-Member of several European projects METACHEM (FP7 2009-2013), EULASUR (FP7, 2009-2012), COST SIMUFER.
-Leader of bi-lateral projects with Ukraine, Canada, Algeria, Germany, Belgium, Tunisia.
Industrial collaborations
-2009-2015: 2 ANR programs with STMIcroelectronics and LAAS TOULOUSE
-2012-2018: project TOURS2015 funded by the French Ministry of Economy, leaded by STMicroelectronics and including 15 academic labs and public agencies (CEA)
-from 2005, 4 ANR projects with THALES TRT on tunable ceramics and thin films, piezoelectric single crystals and dielectric polymer-oxides composites)
-1992-1995: project with ALCATEL space and THOMSON LCC on the degradation of ceramic capacitors for aerospace.
Scientific production and supervision
Production: 230 papers Total citations 5200 H-index: 42 / 20 proceedings / 5 patents
60 invited lectures, 55 contributed talks
Supervision: 20 PhD at Dijon University then Bordeaux University among which 4 in international co-supervision (Germany, Tunisia) and 2 with industry co-supervision / 5 Post-Docs / member of about 200 PHD and Habilitation evaluation committees of which 100 in Bordeaux and 10 abroad (Belgium, Poland, Portugal, Tunisia, Spain, Germany, Switzerland, Algeria, Luxemburg)
10 Relevant publications (total 230)
Order and disorder in ferroelectric perovskites
1/ Maglione , U.T.Hochli and J.Joffrin Dipolar glass state in KTaO3:Na Phys.Rev.Letters 57 , 436 (1986)
2/ Simon, J.Ravez and M.Maglione Cross-over from ferroelectric to relaxor state in lead-free solid solutions J.Phys. : Condensed Matter 16, 963 (2004)
3/ Mornet, S.; Elissalde, C.; Bidault, O.; Weill, F.; Sellier, E.; Nguyen, O.; Maglione, M. Ferroelectric-Based Nanocomposites: Toward Multifunctional Materials Mater 2007; 19(5); 987-992
4/ Keeble, DS; Benabdallah, F; Thomas, PA; Maglione, M; Kreisel, J Revised structural phase diagram of (Ba0.7Ca0.3TiO3)-(BaZr0.2Ti0.8O3) Applied Physics Letters 102, 092903, (2013)
5/ J. M.Daumont, Q.Simon, E.Le Mouellic, S.Payan, P.Gardes, P.Poveda, B.Negulescu, M.Maglione and J.Wolfman Tunability, dielectric, and piezoelectric properties of Ba(1-x)CaxTi(1-y)ZryO3 ferroelectric thin films Journal of Applied Physics 119, 094107 (2016)
Charged interfaces in dielectrics
6/ Bidault, P.Goux, M.Kchikech, M.Belkaoumi and M.Maglione Space charge relaxation in perovskites Phys Rev B 49 , 7868 (1994)
7/ Artemenko, C. Elissalde, U-C. Chung, C. Estournès, S. Mornet and M.Maglione Linking Hopping Conductivity to Giant Dielectric Permittivity in Oxides Applied Physics Letters 97, 132901 (2010)
8/ Maglione and M.Subramanian Dielectric and polarization experiments in high loss dielectrics: a word of caution Applied Physics Letters 93, 032902 (2008)
9/ Schafranek, S.Payan, M.Maglione and A.Klein Barrier height at (Ba,Sr)TiO3/Pt interfaces studied by photoemission Phys.Rev.B 77, 195310 (2008)
10/ M Maglione, A Theerthan, V Rodriguez, A Peña,Carlota Canalias, B Ménaert and B Boulanger Intrinsic ionic screening of the ferroelectric polarization of KTP revealed by second-harmonic generation microscopy Optical Materials Express 6, 137 (2016)