Events

Organic Spintronics: Influence of Interface Structure and Magnetism

December 14, 2010 at 3pm/36-428

Jagadeesh Moodera
Francis Bitter Laboratory, Massachusetts Institute of Technology

abstract:
The unique properties of organic molecules towards reaching molecular level spintronics, has led to the emergence of the field of organic spintronics. The complexity of the charge and spin transport in organic semiconductors (OS) makes their study extremely challenging. These properties need to be understood in order to reach molecular level spintronics. Their study, rich in fundamental science, should lead the way for exploring their potential for molecular electronics. Little has been explored as yet, and thus necessitating a systematic investigation. The first step towards this goal is to study the role of OS/ferromagnet interfaces and the magnetic behavior, which are critical. Spin tunneling has been successfully observed through a few monolayers to thick films of OS such as Alq3 and rubrene, all the way to room temperature. Combined with magneto- transport results, the spectroscopic and polarized neutron reflectometry studies show unique morphology driven signatures of weakened magnetic behavior of OS/ferromagnet interfaces. The presence or absence of a seed layer dictates the growth morphology of the OS layers which in turn influences the magnetic and structural properties of the interfacial FM layer. As a result of this, interfacial magnetism and the spin injection efficiency are strongly affected. We will discuss our recent progress in this area.

bio:
Dr. Jagadeesh S. Moodera, Scientist and Group Leader, Francis Bitter Magnet Lab, MIT, has over 25 years of research experience with interest in fundamental and applied physics that includes nanospintronics, spin polarized transport and tunneling, thin film magnetism, superconductivity and phase-change semiconductor materials. He pioneered the study of ferromagnet-insulator-ferromagnet tunnel junctions, which are the basis for the current computer hard drives, magnetic random access memory. Visiting professor of Applied Physics Dept., Eindhoven Tech. Univ. (Holland). Collaborator and Distinguished Scientist, Korea Inst. of Science and Tech. Distinguished Scientist, Fujitsu Company, Japan. He serves on the advisory board in many international research programs, has published over 170 articles, and has given nearly 200 invited talks/seminars. Honors and Awards: Fellow of American Physical Society, IBM Research Award, TDK Research Award, IITM Distinguished Alumnus Award (2009), 2008-2010 ACI Award from NSF (USA), Oliver Buckley Prize in Condensed Matter Physics of American Physical Society.