Colloquium Seminar Announcement Prof. Jing Shi University of Utah " Giant Magnetoresistance and Organic Semiconductor Spintronics " Date: Monday, May 2, 2005 55 Roessler Time: 4:10 pm. Abstract: Spin injection/detection and coherent spin transport are key ingredients in Spintronics, which were first demonstrated in the giant magnetoresistance or GMR effect in all-metal systems. In spite of remarkable advances in Spintronics, full electrical spin injection and detection has yet to be achieved using conventional inorganic semiconductors. In this talk, I will present our recent progress in Spintronics using a different kind of materials: organic semiconductors. In spin valves consisting of two ferromagnetic layers (La2/3Sr1/3MnO3 or LSMO and Co) and an organic semiconductor spacer (Alq3), we have successfully shown electrical spin injection/detection and coherent spin transport through the GMR effect. In addition, we have also found a high-field magnetoresistance effect in these structures. Our work shows that this high field effect originates from the field-dependent carrier injection due to the anomalous Fermi level shift in double exchange ferromagnets such as LSMO.

E-Mail: jshi@physics.utah.edu
Web Page: http://www.physics.utah.edu/~mohit/toppage.html