Dragan Damjanovic

MXD 236 (Bâtiment MXD)
Station 12
CH-1015 Lausanne

Administrative data

Infoscience publications

Other publications


Current research interests

The research is focused on properties of ferroelectric, piezoelectric and other multifunctional materials. I investigate experimentally physical processes taking place at different length and time scales and how they affect macroscopic behavior of ceramics, single crystals and thin layers. My interests include interaction of atomic defects with domain walls, symmetry breaking on atomic, mesoscopic and macroscopic scale, interface dynamics, dispersion, nonlinearity and hysteresis in a material response, phase transition related instabilities, and structure / microstructure - property relations. 
 Present projects include investigation of emergence of electro-mechanical coupling in complex oxides, properties of complex oxides at cryogenic temperatures, opto-thermo-mechano-electrical coupling in hybrid organometallic perovskites, morphotropic phase boundary systems, electro-mechanical coupling beyond piezoelectricity, and electro-thermal coupling. Besides the fundamental investigations, my research is also application oriented and my group contributes to the development of new materials for sensors, actuators and ultrasonic transducers and new applications for existing materials.

Selected new results

 published in Nature Materials Vol. 17, p. 814, 2018 (doi:110.1038/s41563-018-0116-3)
 Long-range symmetry breaking in embedded ferroelectrics
 H. Simons, A.B. Haugen, A.C. Jakobsen, S. Schmidt, F. Stöhr, M. Majkut, C. Detlefs, J.E. Daniels, D. Damjanovic, H.F. Poulsen
 The characteristic functionality of ferroelectric materials is due to the symmetry of their crystalline structure. As such, ferroelectrics lend themselves to design approaches that manipulate this structural symmetry by introducing extrinsic strain. Using in situ dark-field X-ray microscopy to map lattice distortions around deeply embedded domain walls and grain boundaries in BaTiO3, we reveal that symmetry-breaking strain fields extend up to several micrometres from domain walls. As this exceeds the average domain width, no part of the material is elastically relaxed, and symmetry is universally broken. Such extrinsic strains are pivotal in defining the local properties and self-organization of embedded domain walls, and must be accounted for by emerging computational approaches to material design.
 published in Nature Materials Vol. 16, p. 322, 2017 (doi:10.1038/nmat4799) (full text)
Domain-wall conduction in ferroelectric BiFeO3 controlled by accumulation of charged defects
Rojac Tadej, Bencan Andreja, Drazic Goran, Sakamoto Naonori,Ursic Hana, Jancar Bostjan, Tavcar Gasper, Makarovic Maja, Walker Julian, Malic Barbara, Damjanovic Dragan, 
Mobile charged defects, accumulated in the domain-wall region to screen polarization charges, have been proposed as the origin of the electrical conductivity at domain walls in ferroelectric materials. Despite theoretical and experimental efforts, this scenario has not been directly confirmed, leaving a gap in the understanding of the intriguing electrical properties of domain walls. Here, we provide atomic-scale chemical and structural analyses showing the accumulation of charged defects at domain walls in BiFeO3. The defects were identified as Fe4 cations and bismuth vacancies, revealing p-type hopping conduction at domain walls caused by the presence of electron holes associated with Fe4 . In agreement with the p-type behaviour, we further show that the local domain-wall conductivity can be tailored by controlling the atmosphere during high-temperature annealing. This work has possible implications for engineering local conductivity in ferroelectrics and for devices based on domain walls.
published in Applied Physics Letters, Vol. 110, p. 192905, 2017 (doi:10.1063/1.4983366])
Nonlinear dynamics of polar regions in paraelectric phase of (Ba1-x,Srx)TiO3 ceramics
S. Hashemizadeh and D. Damjanovic, 
The dynamic dielectric nonlinearity of barium strontium titanate 
(Ba1-x,Srx)TiO3 ceramics is investigated in their paraelectric phase. With the goal to contribute to the identification of the mechanisms that govern the dielectric nonlinearity in this family, we analyze the amplitude and the phase angles of the first and the third harmonics of polarization. Our study shows that an interpretation of the field-dependent polarization in paraelectric (Ba1-x,Srx)TiO3 ceramics in terms of the Rayleigh-type dynamics is inadequate for our samples and that their nonlinear response rather resembles that observed in canonical relaxor Pb(Mg1/3Nb2/3)O3.



"Electrically and optically induced strain in single crystals of hybrid perovskites (methylammonium lead halides)", an Office of Naval Research- Global project (2019-2020)

"High performance piezoelectric Micromachined Ultrasonic Transducer for finger print detection" an Innosuisse project with Piemacs  and The School of Management and Engineering Vaud (2018-2019)
"Contribution of polar nano-regions to the large piezoelectric response in Pb-based relaxor ferroelectrics", an Office of Naval Research Global project (2018-2020)

Organization of the International Symposium on Piezocrystals and Their Applications,  Office of Naval Research-Global funding (2019)
"Emergence of electro-mechanical response", a Swiss National Science Foundation project (2017-2021)


"Ultrasonic Speed-of-Sound Sensor Platform" a Swiss-UK Eurostars project (with Rueger, Switzerland, and Ionix, UK) (2016- 2018)
"Origin of the macroscopic symmetry breaking in centrosymmetric phases of perovskite oxydes", a Swiss National Science Foundation project (2015-2017)
"Development and fabrication of a modular energy harvesting platform using electromagnetic and multilayer piezoelectric converters" a Swiss CTI project (with Namiki Precision of Europe) (2015- 2017)
Industrial Grant, Murata, Japan (2014-2016)
Industrial Grant, Adamant, Japan (2014)
"Universal ultrasonic broad-band system " a Swiss CTI project (Engotech, Berner Fachhochschule) (2012- 2013)
PiezoInstitute, EC virtual institute - Coordination and support action (2012-2015).
"Electro-mechanical coupling in lead-free materials and composites: piezoelectric solution and beyond", National Research Program "Smart Materials" - PNR62 project (2010-2012, 2013-2015)
"Novel technology for HIgh-PERformance piezoelectric Actuators - HiperAct" European FP7 Collaborative Project - Large-scale integrating project (Partners include: Noliac, Denmark; IJS, Slovenia; Technical University of Darmstadt, Germany; Piezoceram, Czech R; IPU, Denmark; Gwent Electronic Materials, Great Britain; Tecan, Great Britain; Risoe National Laboratory, Denmark; Vestas Wind Systems, Denmark; Leibniz Universität Hannover, Germany; Hesse & Knipps; Germany; Fraunhofer Institute - LBF, Germany; ContiTech Vibration Technology, Gemany; Ricardo Deutschland, Germany; (2008-2011/2012). (with Dr. Enrico Colla).
"Broad-band electro-elastic response of ferroelectrics: lead free materials " Swiss National Science Foundation (FNS) project (2009-2011)
"Analysis of phase transition behavior in lead-free piezoelectric materials ", Swiss Science and Technology Cooperation Programme with Russia (2010)
"Multifunctional and integrated piezoelectric devices-MIND" European FP6 Nework of Excellence (Partners include: Ferroperm, Denmark; IJS, Slovenia; Ecole Central Paris, France; University of Tours-LUSSI, France; Centro Richerche Fiat, Italy; Instituto de Ciencia de Materiales de Madrid (ICMM)-CSIC, Spain; Cranfield University, UK; Siemens Corporate Technology, Germany; National Physical Lab., UK; Institute of Solid State Physics, Latvia) (2005-2007, extended to 2009).
"Broad-band electro-elastic response of ferroelectrics: understanding hardening and softening processes " Swiss National Science Foundation (FNS) project (2007-2009)
"Bioactive synthetic piezoelectric composites" EPFL College of Engineering Seed Fund (2008)
 (funds awarded but not used)

"Inexpensive, high-performance, lead-free piezoelectric crystals and their applications in transducers for ultrasonic medical diagnostic and industrial tools and equipments-IMMEDIATE" European FP6 CRAFT project (Partners include: Ferroperm, Denmark; IJS, Slovenia; Imasonic, France; FEE, Germany; MTB Zurich; CERAM, Sweden)(2005-2007). Project web page: http://lc.epfl.ch/lc/electro/Projects/ImmediatePublic/Home.htm
"Electromechanical response in ferroelectric materials- Toward unified description of nonlinearity and frequency dispersion of electro-mechanical properties in ferroelectric materials" Swiss National Science Foundation (FNS) project (2004-2005)
"Miniaturized Ultrasonic, Engineered-Structure and LTCC-based devices for Acoustics, Fluidics, Optics, and Robotics - MINUET "European FP6 STREP project (Partners include: Ferroperm, Denmark; FIAT, Italy; IJS, Slovenia; Lego, Denmark; Ecole Central Paris, France; University of Tours, France; Imasonic, France; Tally, Germany; MTB Zurich; ) (2004-2007).
"Electromechanical response in ferroelectric materials-Piezoelectric anisotropy and disorder effects" Swiss National Science Foundation (FNS) project (2002-2004)
"Extrinsic electromechanical response in ferroelectric materials-Domain wall contributions" Swiss National Science Foundation (FNS) project (2000-2002)
"High sensitivity novel piezoceramics for advanced applications - textured, thick films, and multilayer structures - PIRAMID" European 5th Framework GROWTH Program project (Partners: G.I.P. Ultrasons, F; THALES (Thomson-CSF) - Laboratoire Central de Recherches, F; Ferroperm A/S, DK;Josef Stefan Institute, SI;Instituto de Ciencia de Materiales de Madrid (ICMM)-CSIC, E; SINTEF Materials Technology; N;Nanomotion Ltd, IL;Xaar Jet AB, S; Thomson Marconi Sonars SAS, F;Brüel&Kjaer Sound & Vibration Measurements A/S, DK;Vermon SA, F; Iskraemeco dd., SI; Medizintechnik Basler AG, CH) (2001-2004)
"Lead-free piezoelectric materials-LEAF" European 5th Framework GROWTH Program project (Partners: Jozef Stefan Institute-Ceramics Laboratory, Slovenia; Consejo Superior de Investigaciones Cientificas, Spain; Forschungszentrum Jülich GmbH, Germany; GIP "Ultrasons", France; Simrad AS, Norway; Ceram AB, Sweden; Karl Deutsch Prüf- und Meßgerätebau GmbH & Co., Germany; Ferroperm, Denmark) (2001-2003)
"Development of relaxor-based improved piezoelectric single crystals-DORIS" European 5th Framework GROWTH Program project (Partners: Vermon, Tours, France; MATECK, Julich, Germany; FEE, Idar-Oberstein, Germany; Institute of Crystal Growth, Berlin, Germany; CEA/CEREM(Center for Studies and Research in Materials, Grenoble, France)(2000 - 2002)
"Piezoceramic sensors for operation under reduced atmosphere "-PICROP European (EUREKA) and Swiss (CTI) project (Industrial partners: Kistler, Winterthur, Switzerland; Ferroperm, Denmark (1999- 2001)
"Extrinsic electromechanical response in ferroelectric materials" Swiss National Science Foundation (FNS) project (1998-2000)
"Reduction of aircraft noise by nacelle treatment and active control." - RANNTAC. European BRITE-EURAM project and co-author and project leader of the Swiss OFES project (Partners: Aérospatiale, France; SNECMA, France; Dornier, Germany; Mercedes-Benz, Germany; Rolls-Royce, United Kingdom; BMW, Germany; Metravib, France; Hispano Suiza, France; Ferroperm Denmark; and 11 other European industries and universities) (1998-2000)
"Piezoceramics for medical applications" - PIMET European (EUREKA) and Swiss (CTI) project (Partners: Medizintechnik Basler, Zurich, Switzerland; ETA, Grenchen, Switzerland; B-K Medical, Denmark; Ferroperm, Denmark; CERDEC, France; Université de Tours, France) (1997-2000)
"Extrinsic electromechanical response in ferroelectric and relaxor materials" Swiss National Science Foundation (FNS) project (1996-1998)

"High temperature piezoelectric pressure sensors." Swiss CERS / CTI (Committee for Innovations in Technology) project (Industrial partner: Kistler, Winterthur) (1992 -1995, 1995 - 1997)
"Piezoelectric sensors and actuators under extreme conditions." European COST (Cooperation on Science and Technology) 503 project (Partners: Ferroperm, Denmark, Quartz & Silice, France; and universities from Slovenia, Spain, Sweden and France) (1993 - 1996)