Title:Thermal stability of the exchange bias ferromagnetic and antiferromagnetic multilayer thin films
Speaker:Professor Chong Kim Ong, Centre for Superconducting and Magnetic Materials, Department of Physics, National University of Singapore
Time:3:00 Pm, Wednesday , Dec 14, 2011
Place: Room 205, Bldg 14, SCUT North Campus
Sponsor: School of Materials Science and Engineering

Abstract:
The exchange bias between a ferromagnet and an antiferromagnet have been extensively studied in the past few decades because of their application in spin-valve based sensors in hard disk industry as well as its intriguing physical origin. Apart from the researches on the exchange bias for spin-valves, a significant number of works focused on the employment of the exchange bias for microwave applications. So far, most investigations of the usage of exchange bias effect for microwave applications have been performed at room temperature. However, temperature dependence of static and dynamic coefficients have proven to be more useful for practical applications, especially for use as electromagnetic absorber. In this talk, we will focus on the investigation of thermal stability of the exchange-biased ferromagnetic and antiferromagnetic multilayer thin films. Effect of antiferromagnetic (AF) dilution on the magnetic properties and microwave characteristics of Fe70Co30/(Mn75Ir25)1-x(Al2O3)x multilayered thin films with the variation of AF thickness will be discussed. A brief introduction of exchange bias will be given.

Brief introduction to Prof.Chong:
Professor Ong graduated from Nanyang University and the Teacher’s Training College in Singapore. He obtained his PhD in 1973 from the University of Manitoba. He joined the Department of Physics NUS in 1981 and become a Professor in 1993. He received the Outstanding Scientist Award, Faculty of Science in 2007 and the Outstanding Researcher Award, NUS in 2010. As a physicist, he directs a group of young scientists in conducting basic research on functional materials, then explores their application into new devices. The sophisticated facilities in their research laboratories have been designed and built in-house, at low cost. They are based on original research, and many of them are not available commercially. Prof Ong is a tireless researcher and educator; he has published more than 450 papers in international journals with a H index of >32, and has recently authored a book entitled “Microwave Electronics” published by Wiley. He has previously supervised 30 PhD and 28 MSc students. The excellent quality of his research activities has been acknowledged world-wide. He is an esteemed fellow of the Singapore Institute of Physics and the Institute of Physics, UK and has served on the Advisory Boards of several international journals. In the local academic community, Prof Ong was the first Vice-President of the Singapore Academy of Science from 1998 to 2000 and the President of the Institute of Physics, Singapore, from 1996 to 2000.