Title: Boosting the Magnetoelectric Coupling Effect in Film Heterostructures by Photon Associated Thermal Treatment
Speaker:Prof. Jungho Ryu (Yeungnam University, Korea)
Time: 9:00am(Tuesday),08/01/2019
Place:Room 506, Building 9, Ming Palace Campus
Organizer: Department of international cooperation, State key laboratory of mechanics and control of mechanical structures, College of Aerospace Engineering. 

The summary of report:
Heterostructured film based magnetoelectric (ME) composites consist of piezoelectric (typically PZT) and magnetostrictive layers are highly desired especially for applications in integrated magnetic/electric devices. The thermal processing, necessary to obtain high quality PZT films with superior functional properties, unavoidably leads to surface oxidation and crystallization of amorphous magnetostrictive metal substrate, and also chemical interdiffusion between two phases. This will deteriorate both of their properties and eventually degrade the ME coupling. Using granule spray in vacuum process (GSV), PZT thick film was deposited on magnetostrictive amorphous metal (Metglas) substrate. The PZT film was annealed with a continuous-wave 560 nm laser radiation to minimize deteriorative effects of general thermal process, such as chemical reaction and/or atomic diffusion, at the interface and crystallization of amorphous Metglas substrate. We have accomplished near-theoretical magnetoelectric performance in laser annealed PZT/Metglas film composites. The thickness dependent dielectric, ferroelectric, and ME properties of the PZT/Metglas composites were found to be related to the corresponding changes in the optical band gap, annealing behavior and crystallization characteristics of the PZT films.
 
Speaker Profile:

Academic/Research Experiences
9/2006-2/2018  

Principal Researcher at functional ceramics research group, Korea Institute of Materials Science (KIMS)
 
3/2014-2/2017
Professor at Department of Materials Science and Engineering, Korea University of Science and Technology (UST), Korea
 
7/2013-10/2013
Visiting Faculty at Center for energy harvesting systems and materials (CEHMS), Dept. Mechanical Engineering, Virginia Tech, USA.
 
3/2011-2/2013
Adjunct Professor, Changwon National University.
 
9/2001–1/2003
Post Dr. Researcher at the International Center for Actuators and Transducers (ICAT), MRL, the Penn State University, USA
 
3/2001–8/2001
Visiting Research Assistant under Prof. Kenji Uchino at the International Center for Actuators and Transducers (ICAT), MRL, the Penn State University, USA.
 
3/2000–2/2001 

Adjunct Research Assistant under Prof. Kenji Uchino at the International Center for Actuators and Transducers (ICAT), MRL, the Penn State University, USA.
 
1997    Teaching Assistant, Dept. Materials Science and Engineering, Yeungnam University, Korea
 
1996     Research Assistant, Dept. Materials Science and Engineering, Yeungnam University, Korea