July 3, 2012
The Data Storage Systems Center hosted two special seminars in June, when it welcomed IEEE Magnetics Society Distinguished Lecturer Gerrit Bauer and MIT Professor Caroline Ross to campus for talks on spin caloritronics and nanoscale magnetic films, respectively.
Bauer is one of four IEEE Distinguished Lecturers, engineering professionals who lead their fields in new technical developments that shape the global community. For the IEEE Magnetics Society, specifically, the distinguished lecturer exhibits excellence in the field of magnetics — not only in research, but also in developing the applied or technical aspects of the field — and outstanding communication skills.
Bauer's June 20 talk, "Spin Caloritronics," was co-sponsored by the DSSC, the IEEE Magnetics Society Pittsburgh Chapter, and the departments of physics and electrical and computer engineering. In the talk, Bauer addressed the basic physics of spin caloritronics — the science and technology of controlling heat currents by the electron spin degree of freedom — beginning with an introduction to thermodynamics and Onsager's reciprocity relations to build a foundation to describe several recently discovered spin-dependent effects in metallic nanostructures and tunneling junctions. Next, he described how different classes of spin caloritronic effects exist that can be explained only by the collective spin dynamics in ferromagnets, and how these effects can be formulated by scatter theory of transport in adiabatic approximation for magnetization dynamics and computed in terms of material-dependent electronic structures. He noted that issues for further consideration include the relation between electric, thermal and acoustic actuation, as well as the application potential of spin caloritronics.
"We always enjoy having the IEEE Magnetics Society Distinguished Lecturers come to campus. True to his charge, Dr. Bauer was tutorial and introduced many in the audience to an important new area with a clear and very accessible presentation," said DSSC Associate Director Jim Bain.
A fellow of the American Physical Society, Bauer holds a degree in chemical technology from Twente University in the Netherlands, and a doctorate in physics from Technical University Berlin. After serving as a member of the scientific staff at Philips Research Laboratories, he joined Delft University of Technology as a professor of physics in 1992. In 2011, he was appointed a professor of physics at Tohoku University in Japan. He has co-authored more than 200 refereed scientific papers in condensed matter physics, and has spent the last two decades mainly pursuing research in the magnetoelectronics/spintronics area. He's received numerous awards, including the Outstanding Referee Award from the American Physical Society and the Lars Onsager Medal from the Norwegian University of Science and Technology.
On June 21, Ross, a professor in MIT's Department of Materials Science and Engineering, joined the DSSC for a seminar on "Magnetic Nanostructures for Data Storage and Logic." Co-sponsored by the DSSC and Carnegie Mellon's Electrical and Computer Engineering Department, the talk examined the behavior of domain walls in narrow rings and wires made from magnetic films and multilayers. These domain walls can serve as data bits and be created, moved and eliminated using fields and current pulses. Ross discussed domain wall behavior at high frequencies, interactions between walls, and their application in logic and memory devices. She also described recent research results on the development of thin film magnetooptical isolators for integrated photonic systems made from magnetic oxide films.
"Professor Ross showed very interesting results on the manipulation of magnetic domain walls with current, which we believe, based on our own research in the area, may be the basis of some important new classes of non-volatile logic devices," said DSSC Director and ABB Professor of Engineering Jimmy Zhu.
Ross has been a professor in the Department of Materials Science and Engineering at MIT since 1997. Prior to her time at MIT, she worked in research and development for a computer hard disk manufacturer in San Jose, Calif. She holds a bachelor's degree and Ph.D. from Cambridge University in England, and spent time as a post-doc at Harvard University. She is a fellow of the Materials Research Society, the American Physical Society and the UK Institute of Physics.