Technical Description: Research on organic spintronics has gained momentum in the past few years. An important advantage of organic materials is the intrinsically long spin-lifetime because of the small atomic numbers, resulting in less spin-orbit interaction. Strong organic magnetoresistance response as high as 300% has recently been reported. The roles of spin injection and carrier recombination in organic light emitting diodes have also been extensively observed. While the potential is high, there remain challenging fundamental issues, including the mechanisms governing spin injection and spin flip. It is well recognized that interfaces are critical in organic spintronics. The knowledge gap in understanding of the fundamental processes in organic spintronics must be bridged to realize its potential. The goal of this project is to investigate spin injection and relaxation dynamics to understand the underlying fundamental mechanisms important for the development of organic spintronics. The spin injection efficiency is investigated for the interface between various inorganic substrates and organic materials, and the spin relaxation dynamics are studied in organic semiconductor thin films. The primary tool for the investigation is spin-resolved photoemission spectroscopy, supported by other surface analytical techniques including ultraviolet and x-ray photoemission spectroscopy, inverse photoemission spectroscopy, scanning tunneling microscopy, atomic force microscopy, and magnetic force microscopy.
Non-Technical Description: The project is on fundamental materials research of spin injection and relaxation in organic semiconductors. Success of the project can enhance the understanding of the nature of spin-related phenomena in molecular system, with potential impact on organic spintronics for future information technologies. The impact also comes from training of the next generation of scientists in a fast advancing field with international experience and leadership. A major focus of the project is educating and training scientists in an interdisciplinary field including organic electronic materials, surface and interface analysis, ultrafast dynamics, and spintronics. A strong emphasis of the program is on increasing participation of women through programs including University of Rochester Women in Science and Engineering and Pre-College Experience in Physics for high-school students.
This project is co-funded by the Electronic and Photonic Materials Program (EPM) and the Condensed Matter Physics Program (CMP).